Why does my Jeep Cherokee have no spark?

Why does my Jeep Cherokee have no spark?

I have no communication to the computer with a scanner, no check engine light, no 5 v reference, no spark. I have tried to manually pull codes with the key. The dealer says that it does not have an immobilizer by the VIN number. I have power and grounds to the PCM connectors.

What to do if your Jeep doesn’t start?

Check for battery power on two terminals in the relay socket with the key in the start position. If you don’t see battery power, check fuses 6 30A and 26 15A in the PDC. If you see battery voltage, check for ground on pin 85 in the relay socket.

How do you know if your check engine light is flashing?

Leave the key in the run position. The check engine light will turn on for a few seconds, then turn off, then (sometimes after 20-30 seconds) start flashing. The flashes are counting out 2-digit trouble codes.

What does the Check Engine light on a jeep mean?

When a late-model, computerized Jeep is having engine problems, one of the ways it communicates these problems back to the driver is to turn on the “check engine” light on the dash. One idiot light isn’t very descriptive, so Jeep also provided a method to query the computer for all codes that have been set.

I have no communication to the computer with a scanner, no check engine light, no 5 v reference, no spark. I have tried to manually pull codes with the key. The dealer says that it does not have an immobilizer by the VIN number. I have power and grounds to the PCM connectors.

Why does my Jeep Cherokee crank but not start?

Re: Cranks but will not start, no PCM function. You still don’t have spark or injector pulse; this should be looked into first. It still could be a bad crank sensor. The crank sensor sends the pulse to the PCM and then it sends the signals to the proper areas like spark, fuel relay, and injector pulse.

Where is the ignition switch located on a Jeep Cherokee?

When the ignition switch is in either the START or RUN position, it connects circuit A1 from fuse 8 in the Power Distribution Center (PDC) to circuit A21. Circuit A21 powers circuit F99 through PDC fuse 18.

How does the PCM work on a Jeep Cherokee?

When the PCM grounds the ASD relay, contacts inside the relay close and connect circuit F5 from fuse 20 in the PDC to circuit A142. Circuit A142 splices to the generator field terminal, fuel injectors, ignition coil and the upstream and downstream heated oxygen sensors. Circuit A142 also connects to cavity C12 of the PCM.

What to do when your Jeep Cherokee won’t start?

The first thing to check when the engine won’t start is to see if you have spark at the spark plugs. When the car won’t start and you have a spark at the spark plugs then the problem would most likely be in the fuel system. Checking fuel pressure would be next and also checking to see if you have an injector pulse at the fuel injectors.

What are the input signals in a pulse injector?

These are the Ne, G, and IGf signals. Inside the ECU, the Ne Signal is used to produce an injection chive signal. The G signal is used to determine the timing of the injection signals. The IGf signal is monitored for fuel delivery fail-safe. (With Conventional EFI, the IG signal is used to produce the injection drive signal.)

When the ignition switch is in either the START or RUN position, it connects circuit A1 from fuse 8 in the Power Distribution Center (PDC) to circuit A21. Circuit A21 powers circuit F99 through PDC fuse 18.

The first thing to check when the engine won’t start is to see if you have spark at the spark plugs. When the car won’t start and you have a spark at the spark plugs then the problem would most likely be in the fuel system. Checking fuel pressure would be next and also checking to see if you have an injector pulse at the fuel injectors.

Re: Cranks but will not start, no PCM function. You still don’t have spark or injector pulse; this should be looked into first. It still could be a bad crank sensor. The crank sensor sends the pulse to the PCM and then it sends the signals to the proper areas like spark, fuel relay, and injector pulse.

Why does my Jeep 4.0L have no spark?

It’s almost impossible for all 6 COP ignition coils to fail at the exact same time… so the most likely cause for this no spark condition is a bad crankshaft position sensor. But before you go out and replace the crank sensor, you need to test it (to make sure it’s fried).

Can a spark test be done on a no start Jeep?

Testing for spark can very easily and safely be done with a dedicated spark tester. If the ignition system is the cause of the cranks but does not start condition, you’re not gonna’ see spark at any of the 6 spark plug wires or 6 COP ignition coils.

Why is my fuel pump not working on my Jeep?

Confirming power to the fuel pump (with a multimeter) also verifies that the fuel pump has failed and needs to be replaced. If no voltage is present, as your helper cranks the engine, then the cause of lack of fuel condition is due to either a bad fuse, fuel pump relay.

Why is my brake light not working on my Jeep Grand Cherokee?

Jeep Grand Cherokee brake light not working – fixed! – YouTube If playback doesn’t begin shortly, try restarting your device. Videos you watch may be added to the TV’s watch history and influence TV recommendations.

Why are there no parking lights on my 92 Cherokee?

92 cherokee limited No Parking Lamps,Dash,lights! Well this started after the battery went dead. First the head lamp flashed after installing new battery. reset security with key lock and unlock drivers and passenger door. Head lamps stopped flashing after locking and unlocking passenger door.

What to do if your Jeep wont start with no power?

Got one one day ,then went to go to work the next morning and BAM it’s as if his battery was drained. Lights came on very faint and all we got was small clicks. New key ignition unit and the thing worked perfectly again. Also, your Jeep will not start if you have no power going to anything.

Why does my Jeep Cherokee not turn on?

Vehicle does not turn over or even click like a low battery but all the lights and everything come on. If I use the remote start, car starts just fine or shift down to neutral and then try to start. I did just have my gear shifter replaced about two months ago under warranty so I wonder if something was tightened all the way.

Where does the power supply go on a Jeep Cherokee?

There is a wire that goes to the power distribution box on the finder close to the battery, if you don’t have power to it nothing will work. Could be a dirty connection there or there is also a large main fuse in the PDB that supplies power to all circuits in the jeep.

Why is my 2016 Jeep latitude not starting?

My 2016 Jeep Cherokee Latitude is suddenly not starting. When I push the light flash. I had AAA come out because I thought it was the battery but the battery is fine. We also simulated installing a new battery to reset the

How to know if your engine has no spark?

First Confirm Your Engine Has No Spark. 1 Disable the fuel system by removing the fuel pump fuse or relay. 2 Insert a spark plug tester into the plug boot and ground it on a piece of metal on the engine. 3 Finally, Have someone crank the engine and watch for spark.

Why does my Jeep 4.0L have no start?

CASE 2: Spark was NOT present in all of the cylinders (DISTRIBUTOR TYPE): This test result tells you without a doubt that the no start condition of your 4.0L equipped Jeep is due to a malfunction in the ignition system. Now, with no spark in any of the engine cylinders, this what I would suggest:

What happens when you hit the gas on a Jeep Cherokee?

As you hit your Cherokee’s gas pedal, the fuel and ignition systems respond. If acceleration has diminished, it should be felt. The less cylinders that your engine has, the more that one cylinder not firing properly will have an effect on engine performance.

Is there a problem with the ignition on a Jeep Cherokee?

If there is one common denominator amongst practically all 1984 to 1996 Jeep Cherokees (XJ , ZJ, WJ and WK’s alike) it is a bad ignition. Though typically robust, most Jeep Cherokees will eventually experience ignition failure, leaving otherwise happy owners stranded.

Can a Jeep Cherokee turn off on its own?

145 people found this helpful. It turns off on its own and it wont turn on right away and sometimes it wont even turn on till a day later or so 113 people found this helpful.

How to test the crankshaft position sensor ( Jeep 4.0L )?

How To Test The Crankshaft Position Sensor (1994-1996 4.0L Jeep). Checking that the fuel pump is delivering fuel to the fuel injectors is not that hard on your 4.0L equipped Jeep since the fuel injector rail comes equipped with a Schrader valve (this is the valve to which you can connect a fuel pressure gauge).

When the PCM grounds the ASD relay, contacts inside the relay close and connect circuit F5 from fuse 20 in the PDC to circuit A142. Circuit A142 splices to the generator field terminal, fuel injectors, ignition coil and the upstream and downstream heated oxygen sensors. Circuit A142 also connects to cavity C12 of the PCM.

Are there any problems with the Jeep 4.7 engine?

For many years, 4.7 engines have been able to provide excellent satisfaction to a large number of users. However, not all that glitters are gold. In this case, we will refer to the most common Jeep 4.7 engine problems that are usually suffered. Our goal here is not to focus on the Jeep criticism.

Why is my Jeep engine not working properly?

Here there is a very common problem that hinders the power output. In general, this is a well-known problem for Jeep users. Here we can detect that the performance of the engine decreases considerably. At the same time, the oil used inside the engine becomes too thick.

Why do I keep getting zero pressure codes on my Jeep?

But I kept getting the following error codes: The requested pressure and the actual pressure are not within a tolerance band for the Governor Control System which is used to regulate governor pressure to control shifts for 1st 2nd and 3rd gear (Zero Pressure Malfunction).

Is the AW4 transmission on the Jeep XJ Cherokee?

Diagnosis of faults in the Jeep AW4 transmission. The automatic transmission used in the Jeep XJ Cherokee is nearly bullet proof. Seldom does it ever give trouble.

How to troubleshoot a no start Jeep 4.0L?

More specifically, this means that troubleshooting the problem requires that you check and confirm that: All 6 cylinders are getting spark (with a spark tester). That the fuel pump is creating enough fuel pressure. And if necessary, check the engine’s health with a compression test. I’ll go into more specific details in the following headings: 1.)

Why does my Jeep turn over but does not start?

Cranks But Does Not Start Condition: In this type of condition, you turn the key and the engine in your Jeep cranks (turns over) but it doesn’t start (run). The usual suspects, that can cause this type of problem, are a bad fuel pump, bad crank sensor, bad ignition coil (if your Jeep is distributor equipped), etc.

What kind of engine does a Jeep Cherokee XJ have?

Some drivers faced the engine overheating and a raw gas odor. In 1991 the Cherokee XJ gained the High-Output version of the 4.0-liter engine. It came equipped with a multi-port fuel injection system to produce 190 hp. This was pretty much the only change it saw for nearly a decade, until 1999.

When did the Jeep Cherokee XJ come out?

The Jeep Cherokee (XJ) is a compact SUV that was manufactured and marketed by Jeep from 1997 to 2001. Sharing the name of the original full-size SJ model, but without a traditional body-on-frame chassis, the XJ instead featured a light-weight unibody design. Idle problem remains a odd frustrating headache after much work.

What causes low engine RPMs on a Jeep Wrangler?

Low engine RPM’s and high carbon deposits are associated with short trip driving where the vehicle engine is not allowed to fully warm to normal engine operating temperatures.

How can I tell if my Jeep Wrangler has a misfire?

Cold ambient temperatures will increase engine warm-up time and add to the opportunity of carbon deposit build-up on the stem of the engine exhaust valve.2.Verify that an engine misfire condition is present. Use of the DRBIII (R) during a road test, or a Co-Pilot data recording, may help to determine engine misfire and misfire counts.

What causes the fuel pump to not start?

The fuel pump is running and delivering normal pressure to the engine But, with all that working your engine still will not start. So, the most likely cause, is that the fuel injectors are probably not opening. The (PCM) uses the trigger signal from the crankshaft position sensor; and/or camshaft position sensor to pulse the injectors.

What causes no start on a jeep 4.0L?

Updated: 29 June 2019. Article Id: 420. A no start condition, on your 4.0L Jeep, is usually caused by a lack of fuel, or a lack of spark, or a lack of air (generally engine compression).

What kind of ignition system does a Jeep Cherokee use?

The ignition system is the one tasked with creating and delivering spark to each of the 6 cylinders. Without spark, the engine will crank but no start. The ignition system of the Jeep vehicles covered by this tutorial use either a distributor type system or a COP (Coil-On-Plug) ignition coil system. Failed ignition coil.

What to do if your Jeep has no spark?

Now, with no spark in any of the engine cylinders, this what I would suggest: Check for spark directly on the ignition coil tower using a spark tester (if distributor equipped).