Marklar024

Driving down the highway yesterday, normal cruise speed, and all the sudden the motor cuts out...All electronics are still working, turns over but won't fire up. Have fuel, but no spark from the coil. Any ideas?

cruiser54

Probably a failed CPS.

freegdr

Codes are ? My 94 it was the cam/hall effect sensor disenegrated . Could go either way...

hajenkadenkados

I'm with Cruiser on the CPS. Been there, done that, got the thread.
https://www.cherokeeforum.com/f2/eng...riving-129926/

Marklar024

Thanks for the help, haven't had a chance to check codes (my mechanic has been too damn busy to come over and fix it.) gonna start on the CPS now. Almost every post in the forums point to it being the CPS, I've checked all the fuses and followed every wire to look for shorts but nothing. I was gonna take out the coil and have it tested, but with the responses I'm getting and what I've read, I'm gonna start with the CPS. Let you know if this fixes the problem

Marklar024

Replaced the CPS with no luck. Gonna pick up and ignition coil now(old one had cracks all over) and try that. At least it's a much cheaper fix.

RTorrez1

Did you get your CPS from the dealer? If not it still may be your problem. After market one are garbage. They are hit and miss with a lot more miss then not and if they do work they will normally fail in a short time.

Marklar024

No didn't get it from the dealer, but also changed out ignition coil as well and again no luck. Think it has to do with the PCM, I checked ON-OFF-ON-OFF-ON method to check the codes again and came up with, CODE 12: Direct battery input to PCM was disconnected within the last 50 Key-on cycles.
What does this mean exactly? And what would I do to fix this issue?
Would go check it out now, but it's a bit to late right now and it's cold as hell.

caged

12 is pretty common when checking for codes, it usually begins the cycle. it's the others that i usually concentrate on, like 11, 21, then ends cycle with a code 55.

are you getting any other codes?

Radi

Grab a test light and verify power to the coil connector + terminal with the key ON.
Then check the coil - terminal while cranking. It should 'blink' as the PCM grounds the - line to fire the coil.

Code 12 just means you disconnected the battery within the last 50 key on cycles.
If you did not disconnect the battery, start checking the wiring harness that supplies power to the PCM, grounds, battery cables, etc.

Marklar024

CAGED:
Other codes that are now coming up
22 Engine coolant temperature sensor above or below acceptable voltage.
23 Intake air temperature sensor input above or below acceptable voltage.
24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.

Radi:
I'm gonna check on that again as soon as I get my coffee, too damn early to function without it. Went over all of the wires, grounds, and harnesses once but will def be sure to check again.

Thanks for the help everyone, Hopefully I can get this issue resolved as soon as possible. At least I'm keeping busy working on my Jeep

Marklar024

Coil is getting power but no spark coming out? Replaced coil already possible it was bad? Wasn't the cheapest they had, but also wasn't the best.

CCKen

Those three items listed share the same ground through a splice in the fuel injector wiring manifold.

The MAP sensor ground ties into this ground circuit at a splice in the large wire loom running along the firewall.

Sometimes wiggling wire harnesses will show you where the problem exists. Try the two areas I mentioned.

Marklar024

Yes getting a flash from the test light when turning the engine, but still no juice coming out of the coil. I just bought it, but i know they have a tendancy to not work sometimes, I was going to put the original coil back in but it wasn't sparking either, which leads me to belive that the coil I bout somehow was no good?. I had tried a new CPS but no luck, wires going to CPS are fine and not melted or shorting and are properly grounded. Other than a bad CPS or bad Coil, What could cause the coil not to send out spark to the distributor? Distributor spins when cranking and seems to be in good condition. Could it possibly be in the ignition?

Radi

So you have steady power to the coil + terminal and blinking while cranking at the coil - terminal?