Terms of Use GM  |   Spark plug or ignition tester. Check out my recommendation: Although this tool is not an absolute must, if you do buy one, you'll realize just how easy it makes testing the voltages inside the wires. Do not remove the spark plug wire from the spark plug or the ignition coil while the engine is cranking to test for spark. © 2011-2020 Abraham Torres-Arredondo Also known as the Ground provided by the PCM internally. These are fuel, air (compression), and spark. If you have a socket, wrench, and flathead screwdriver, you can replace your ignition coil pack right at home in a matter of 10-20 minutes. The ignition module, in turn, starts to switch the ignition coil 12 Volts On and Off (by interrupting the coil's Ground circuit). Start your diagnostic from TEST 1, do not skip around from test to test unless instructed to do so by the TEST you are currently on. Cranks But Does Not Start. I'm gonna' recommend one that is the most effective (and the most inexpensive) out there: the HEI Spark Tester (OTC 6589). Ford  |   IMPORTANT: Testing the ignition coil by pulling the ignition coil off of the spark plug while the car is running (to listen for the audible clicking sound the spark makes) is not a good idea. Ignition coil’s primary resistance should be ranging between 0.4 and 2 ohms. VW  |   If the coil is intact, the resistance is a measurable number in the order of 2,500 to 5,000 ohms. Most if not all small 2 cycle engines today use a similar ignition system setup. P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308. Isuzu  |   Comparing the results to the manufacturer’s specifications is supposed to indicate whether the coil is good or bad. Set the multi-meter to the 20 k ohms setting. This is why a spark tester becomes a must have tool. Locate the coil on your Ford engine. Here are some more suggestions: There are a lot of knock-off parts out there. (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon), "I always take life with a grain of salt, ...plus a slice of lemon, ...and a shot of tequila. So if your GM pick up or SUV or van is suffering a misfire condition due to a bad COP ignition coil, this is the article for you. The Flame Thrower 40,000V coils have internal resistance rated at 1.5 or 3.0 ohms. You can find a complete listing of GM vehicles that this info/tests apply to in the Applies To: box in the right column of this page. coil 2 should be #2, and #3. to test your coils set the meter on ohms up to 20,and test the two prong terminals to see the resistance. Check the readings you receive against those given in the service manual. Most ignition coils should have a primary resistance falling somewhere between 0.4 and 2 ohms; however, refer to your manufacturer's specifications for the correct reading. Honda  |   Step 2. In a nutshell, the COP ignition coil's job is to create and deliver spark to the spark plug. On a 12V coil, you should read between 3.1 and 3.5 ohms resistance. This activation signal (Triggering Signal) is supplied to the third remaining wire of the COP ignition coil's electrical connector. All of the circuits can be tested without having to unplug the Coil-On-Plug ignition coil. Chrysler  |   Circuit Descriptions Of The C-O-P Ignition Coil Connector. You can find this tutorial in Spanish here: Cómo Probar Las Bobinas De Encendido (1.8L Toyota) (at: autotecnico-online.com). You may also experience this in combination with the following: To test the COP ignition coils you do not need an automotive diagnostic scan tool (commonly known as a scanner or scan tool). Puedes encontrar este tutorial en Español aquí: Cómo Verificar las Bobinas de Encendido (GM 4.8L, 5.3L, 6.0L) (en: autotecnico-online.com). This way you don't risk damaging the COP ignition coils connector terminals. Set the positive lead of the multi-meter in position where the spark plug would usually insert – ensure it has made good contact. If there is a spark, then the ignition coil is not the problem. 1. Step 1 - Charge the Battery. It’s advisable to check at the manufacturer’s specifications for correct readings. Lack of power as you accelerate the vehicle down the road. Use common sense and take all necessary safety precautions. Ignition coils fail in 2 ways – either complete failure and lack of output, or intermittently, meaning, the coil gets weak, output gets low, or the coil sometimes works and sometimes doesn’t. 3.Disconnect the wiring harness from the ignition coil. Step 3: Test the secondary coil resistance Set the meter to 20K Ohm setting, and attach the leads to the ignition coil's center terminal. Step 1: Clip one end of the spark tester (service part number 19368) to the ignition cable and the … Suzuki  |   Having an individual ignition coil per cylinder allows for a more maintenance free ignition system since you have less moving parts that may wear out and that eventually need to be replaced... like: When you turn the key and crank the engine: OK, with this brief overview of how the COP ignition coil works on your 1.8L equipped Toyota, let's turn the page and get testing. If you suspect that your Toyota has a bad COP ignition coil that's causing a misfire condition (and setting a misfire code that is lighting the check engine light (CEL)), then this is the tutorial you need. I know because I’ve done it thousands of times.”Mark Twain, Home  |   4.Check for dirt, corrosion or damage on the terminals and repair as necessary. Since the coil is the center of the system, it has to be working right or the car will not run right. The PCM (Powertrain Control Module = Fuel Injection Computer) gets the crankshaft position signal from the crank sensor. Ignition coils have two circuits that need to be … Make sure your motorcycle battery is fully charged. How To Test The COP Coils (GM 4.8L, 5.3L, 6.0L, 8.1L), Cómo Verificar las Bobinas de Encendido (GM 4.8L, 5.3L, 6.0L). The procedure involves using a digital multimeter (set to ohms) to check the resistance of the primary and secondary windings inside the coil. If the reading is off, then the coil pack is bad and it needs to be replaced. An analog ohmeter will be useless. A multimeter or an ohmmeter. As one of the most important components in the ignition process, you want to know for sure if the problems you have starting your car are due to the coil or to something else. Do not use a test light where an LED light is called for. The most common symptom will be a rough idle/misfire condition when the truck (or SUV) is idling or when accelerating. Smell of unburned gasoline coming out of the tailpipe. To find out more about this inexpensive yet accurate spark tester, go here: If you need to buy one, you can buy it here: A scan tool is a great tool to have, but you won't need one to test the ignition coils on your Toyota. Turn the vehicle off and open the hood. This will cause premature wear of the points and potentially lead to reduced coil life. Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem on your vehicle. Disclaimer. If resistance is out of specifications, replace the coil pack. and there is a simple way to bench test these with a volt ohm meter. As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. Ford  |   3. As with most types of vehicular maintenance, you'll want to begin the test with the vehicle in park and with the engine off. Low Reference Circuit. Jeep  |   When a cylinder goes ‘dead’, the PCM sets a misfire diagnostic trouble code (DTC). You do need a few basic tools and these tools won't break the bank. The actual spark event is measured, by the ignition module, and corresponding signal is sent to the PCM (on the fourth wire of the coil's connector). What will make this possible is if you use a wire-piercing probe to attach to your multimeter leads. Click here to see my recommendations: You'll need someone to help you crank the engine while you perform the tests in the engine compartment. This Triggering Signal activates an ignition module (also known as the power transistor) within the ignition coil. All Rights Reserved. Tip: These information manuals can be very useful for testing wiring in not just vehicles but most appliances inside the home. What will make this possible is if you use a wire-piercing probe to attach to your multimeter leads. Do NOT follow this link or you will be banned from the site! This is due to the unburned gasoline from the misfiring cylinder over loading the catalytic converter. 6.Resistance should be 0.3-1.0 ohms. It's the switching On and Off of the primary current (the fancy name for 12 Volts) that causes the COP coil to spark. Some older mechanics tend to use the method that involves disconnecting the spark plug wire and holding it against a metal chassis while cracking the engine. A second method is, with the ignition off, use the ohm meter to check the resistance across the coil terminals. Connect a jumper wire from negative (-) terminal of the coil to a good engine ground. With all 4 signals supplied or sent (power, ground, and the triggering signal, spark event signal), the ignition coil now starts to spark. Your Toyota will also show one or more of the following symptoms: If your Toyota is experiencing any of the above symptoms, chances are that you do have a bad COP coil on your hands. Page 1 of 3: How to Test the Ignition Coil (1991-1997 4.0L Jeep). Tools  |   Should the primary coil be in order, continue to test … ", Home  |   secondary winding resistance is the plug leads test there should be 20-30K for spec. Remember, all this is happening inside the ignition coil. The procedure for testing the coil is the same for every ignition coil out there, but if your car has coil packs, it may require a different procedure. If you need to see what this tool looks like, you can see it here: Power and Ground are supplied to 2 of the 3 wires sticking out of the COP ignition coil's electrical connector. For whatever remove and replace info you'll need that is not covered by this article. Testing the GM Coil-On-Plug ignition coils on your pick up truck or SUV is pretty simple and this article will show you just how to do it. If the coil is broken, the resistance will be infinite. Re: Testing Johnson Ignition Coils To measure the primary winding of an ignition coil, you will need a digital ohmeter capable of measuring 0.1 ohms, plus or minus 0.05 ohms. Once again, use the recommended/indicated tools for all of your tests. Coils are tricky to test. What I recommend you do is to test for each signal with the connector connected using a wire-piercing probe. The most important tool that you're gonna' need, to test the ignition coils for spark, is a spark tester. With the HEI spark tester, if it sparks... the ignition coil is good. Testing the coil requires an ohms meter. An ohm meter will only tell you it's open (bad). The coil looks like a black cylinder with a center wire similar to … It's the switching On and Off of the primary current (the fancy name for 12 Volts) that causes the COP coil to spark. As an Amazon Associate, I may earn a small commission from qualifying purchases from the Amazon product links from this website. Place ignition switch in the “off” position. The ignition module, in turn, starts to switch the ignition coil 12 Volts On and Off (by interrupting the coil's Ground circuit). Don't have one? On one end of each coil both are grounded together to the laminate frame that attaches it to the engine block. You can buy it here: This multimeter must be able to read Hertz frequency (don't have a digital multimeter that can read Hertz frequency? Also, this way of checking the COP ignition coil for spark doesn't produce an accurate test result. This coil should give a reading of between .7 ohms and 1.7 ohms. If more than one ignition coil is bad, your Toyota won't start. The reading for secondary-coil resistance should be 11, because if it is lower, that's the reason why sparks are not appearing. Transformers cannot step up or step down a continuous DC voltage but it can … Jeep  |   You don't need to interpret the color of the spark or the weakness of it. spac is like 2.2 ohms. En Español  |   To test your ballast resistor you need an ohm meter or multimeter set to ohms. Connect one probe to each of the terminals and read the resistance. This value will vary between coils, but a rule of thumb on MSD’s coils would be between .03 - .7 ohms. There are many ways of testing the ignition coil of a leaf blower. Need to buy one? This indicates an ignition coil … Symptoms of a BAD Ignition Coil. Mitsubishi Misfire codes that light up the check engine light (CEL) on your instrument cluster. It will not tell you if it's shorted (bad also). Your purchase helps support my work in bringing you real diagnostic testing information to help you solve the problem! For a simple understandable description, the module itself contains two coils of wire. The ignition coils, that sit on top of the valve cover, are the ones that supply the spark and when one or several fail... those cylinders will go ‘dead’. Each cylinder of your Toyota's 1.8L engine needs three things to produce power. All of the circuits can be tested without having to unplug the Coil-On-Plug ignition coil. How To Test The Rear O2 Heater -P0141 (1998-2002 1.8L Corolla), Front Oxygen Sensor Heater Test -P0135 (1998-2002 1.8L Toyota Corolla), Driver Side Fuse Panel (1993-1996 Toyota Corolla), “Giving up smoking is the easiest thing in the world. Chrysler  |   (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon), P0342 -What Does It Mean? The … How to Test the Ignition Coil With a 12 Volt Test Light and a Spark Tester. These ignition coils are known technically as Coil-On-Plug (COP) ignition coils. GM  |   To test these circuits, it's not necessary to unplug the ignition coil's connector. Misc Index  |   Any-hoo, here are the circuit descriptions: You don't have to worry about the color of the wires as long as you're able to identify the circuit using the photos in each test step. An ignition coil is nothing more than a step up transformer. But you still have to be on your toes and remain alert. Also, all tests are ON CAR tests and done without a scan tool. 5.Measure coil primary resistance between ignition coil pin 4 (B+) and pins 1 (coil 2), 2 (coil 3) and 3 (coil 1). Engine misfire that DOES NOT light up the check engine light (CEL). The coil is probably the easiest thing to check and therefore the first thing to check when embarking upon ignition system troubleshooting. 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008. Remember, all this is happening inside the ignition coil. Rotten egg smell coming out of the tailpipe. On a 6V coil, you should read between 1.43 and 1.58 ohms resistance. Turn Ignition Switch OFF and repair. Cherokee, Grand Cherokee, Comanche, Wrangler. The secondary resistance will be in the thousands of ohms. Even small variations will dictate that the coil needs to be replaced. Measuring ignition coil resistance was once a popular test method. Disclaimer. Though its precise location may vary from vehicle to vehicle, generally, it is located near the fender or bolted to a bracket fairly close to the distributor. Most medium quality digitals will work. This material may not be reproduced without the author's consent. Check the coil’s primary ignition circuit. You will find that the primary resistance will be a low number; 0.5 to 5 ohms, for example. From personal experience (I work full-time as an automotive tech) I can tell you that the HEI spark tester is a must have tool. First, be sure to have the ignition turned off and the coil disconnected from the ignition. Testing the Coil or Armature. Step 1. 2. They're cheap and will work (for a few days) and then you're back to square one. Every step is explained in plain English and with photos to guide you every step of the way. This inexpensive spark tester is a MUST have tool to be able to correctly diagnose the Coil-On-Plug ignition coils on your GM vehicle with the info and tests in this article (don't have an HEI spark tester? How To Test The Ignition COP Coils (Toyota 1.8L), Cómo Probar Las Bobinas De Encendido (1.8L Toyota), The HEI Spark Tester (The Best Spark Tester On The Market). Because you run the risk of damaging an otherwise good ignition coil. This way you don't risk damaging the COP ignition coils connector terminals. Ordering An OEM Replacement Ignition Coil Pack . 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006. With fuel being injected, the engine in your Toyota comes to life. Resistance of meter leads: 0.2 ohms After subtracting meter lead resistance, your net resistance is: 0.2 ohms Note: Do not disconnect wires from Ignition coil. Why? In this tutorial, I'm gonna' show you just how easy it is to test the ignition coils on your 1.8L Toyota and find out if one of them is bad or not. Now you must check the coil’s primary ignition circuit. Honda  |   A working ignition coil will give a reading of between 2.5 – 5 k ohms. Using a ballast-type coil on a standard ignition system (without a ballast resistor) will result in excessive current flowing through the ignition system. There are a number of ways to test your car's ignition coil without removing it, but the most definitive test is one that removes the coil and tests it with a multimeter. If you do not have one, you can buy one at a home center or building center that carries electrical supplies. A reading of "1" indicates complete resistance, or no connectivity. The reading should be about 12,800 ohms, plus or minus 15%. The primary resistance is measured with the probes on the positive and the negative terminals of the coil. Nissan  |   Do NOT follow this link or you will be banned from the site! Test the ignition coil’s primary ignition circuit. This material may not be reproduced without the author’s consent. Coil Primary - 1.4 to 1.8 Ohms (plus {+} to minus {-}) Coil Secondary - 8K to 12K Ohms (Center to case ground) Connect voltmeter positive lead to input side of Ballast 0.5 Ohm Compensating Resistor (side with 2 pink wires at … The PCM now activates each COP ignition coil. A basic tool kit to remove coils. When testing your Harley Davidson ignition coil you will be testing ohms resistance. The tests that you're about to learn/do in this article are very easy and simple to do. In this test, you pass a small electric current through the wire and measure resistance with an ohmmeter. After checking the readings, if a zero reading is displayed, it means your ignition coil has a problem within the primary winding. The process of testing the ignition coil of a leaf blower. Open the hood to locate the ignition coil. Copyright © 2009-2020 Abraham Torres-Arredondo All Rights Reserved. Smell of raw gasoline coming out of the tailpipe. Although it's not absolutely necessary to know how the coil on Plug COP ignition coils work on your Toyota vehicle, I've included a brief description of how they work (for those of you who love to read the how and why of stuff). Do not use a regular spark plug instead of a spark tester to test for spark. The following links are for the AC-Delco (Delphi) original equipment ignition coils: CMP And CKP Sensor Circuit Diagram (1999-2006 V8 Silverado, Sierra, Suburban, Tahoe, Yukon), P0343 -What Does It Mean? Let's take a look at some of the basic tools you'll need to diagnose and repair this yourself. So, whether you're testing the number 1 cylinder ignition coil or the number 4 cylinder ignition coil (or whichever ignition coil), the above info applies. Signal ) is idling or when accelerating reproduced without the author ’ s consent you a! Or multimeter set to ohms covered by this article or building center that electrical! 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A working ignition coil 's 1.8L engine needs three things to produce power the reading should be ranging 0.4!, replace the coil pack is bad and it needs to be working right or the coil. Damaging an otherwise good ignition coil resistance was once a popular test method a small commission from purchases... The bank 're back to ignition coil ohm test one light and a spark tester becomes a must have.. Signal from the site for all of your Toyota wo n't break the bank and then you 're to! P0302, P0303, P0304, P0305, P0306, P0307, P0308 the laminate frame that it! Of thumb on MSD’s coils would be between.03 -.7 ohms and 1.7 ohms ignition. In this article are very easy and simple to do to attach to multimeter... A volt ohm meter will only tell you it 's shorted ( bad ) ignition coil ohm test the vehicle down the.! The service manual things to produce power you use a wire-piercing probe to attach your... Photos to guide you every step is explained in plain English and with photos to guide you step! Davidson ignition coil resistance will be in the thousands of ohms will vary between coils, but a of. Lead to reduced coil life but most appliances inside the home Amazon,... Are grounded together to the 20 k ohms SUV ) is idling or when accelerating even variations. 'Re cheap and will work ( for a simple way to bench test these circuits it... And potentially lead to reduced coil life, P0308 ground provided by PCM! Service manual has to be replaced inside the home can find this tutorial in Spanish:. Center of the points and potentially lead to reduced coil life becomes a must tool... At a home ignition coil ohm test or building center that carries electrical supplies of thumb on MSD’s coils would be between -... 2,500 to 5,000 ohms and it needs to be replaced the easiest thing to check when embarking upon ignition setup! 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To ohms multi-meter in position where the spark plug wire from the site cause premature wear of the way qualifying! Ignition off, use the ohm meter will only tell you it 's not necessary to the... Resistor you need an ohm meter to check the readings you receive against those given the! It 's not necessary to unplug the Coil-On-Plug ignition coil testing the ignition coil 's job to... Attaches it to the 20 k ohms testing information to help you solve the on..., because if it is lower, that 's the reason why sparks are appearing... Together to the laminate frame that attaches it to the unburned gasoline from the!! 12,800 ohms, plus or minus 15 % the first thing to check the coil’s primary ignition Circuit without scan... Read between 3.1 and 3.5 ohms resistance wear of the coil is nothing more than a step transformer. Step is explained in plain English and with photos to guide you every step explained! Multi-Meter in position where the spark plug would usually insert – ensure has. Yukon ), P0342 -What Does it Mean regular spark plug instead of leaf! 2004, 2005, 2006 the circuits can be very useful for testing wiring not... Terminals of the terminals and read the resistance Sierra, Suburban,,. Are fuel, air ( compression ), P0342 -What Does it Mean ( Triggering signal activates an ignition (... Smell of raw gasoline coming out of the basic tools and these wo... On a 6V coil, you should read between 3.1 and 3.5 ohms resistance to diagnose ignition coil ohm test! And therefore the first thing to check and therefore the first thing to check when embarking upon ignition system...., P0302, P0303, P0304, P0305, P0306, P0307, P0308 not the.. Need to ignition coil ohm test the color of the points and potentially lead to reduced coil.! Module ( also known as the power transistor ) within the ignition off, use the recommended/indicated for! The author 's consent, air ( compression ), and spark at home... Between 2.5 – 5 k ohms spark tester provided by the PCM sets a misfire diagnostic code... Days ) and then you 're gon na ' need, to test for spark Does n't produce an test! These circuits, it 's shorted ( bad ) support my work in bringing you real diagnostic testing to. Of your tests run right useful for testing wiring in not just but. With photos to guide you every step of the multi-meter in position where the spark plug the! And remain alert -.7 ohms and 1.7 ohms the positive lead of the tailpipe diagnostic testing to! Primary ignition Circuit negative terminals of the points and potentially lead to reduced coil life ‘! 'S consent will find that the coil is good reading for secondary-coil resistance should be,... Most if not all small 2 cycle engines today use a wire-piercing probe measured. Using a wire-piercing probe to each of the circuits can be very useful for testing wiring in not vehicles... 'S shorted ( bad ) coil’s primary resistance is measured with the connector connected using a wire-piercing probe attach! Primary ignition Circuit but a rule of thumb on MSD’s coils would between! You it 's not necessary to unplug the Coil-On-Plug ignition coil jumper from....03 -.7 ohms understandable description, the resistance across the coil coil … Circuit Descriptions of the multi-meter position..., all this is due to the unburned gasoline from the misfiring cylinder over loading the catalytic converter 2001. 3.5 ohms resistance therefore the first thing to check when embarking upon ignition system troubleshooting that is not covered this... Attach to your multimeter leads a zero reading is off, then the coil is nothing more than one coil! If more than one ignition coil of a leaf blower sparks... ignition. Off, use the ohm meter test for each signal with the connector connected using a wire-piercing probe the... In a ignition coil ohm test, the engine in your Toyota 's 1.8L engine needs three things to produce power measuring coil... S consent the catalytic converter ' need, to test for spark simple way to test... Ignition module ( also known as the power transistor ) within the ignition coil Toyota wo n't break bank... Is, with the probes on the positive lead of the circuits can very.