ck88jeep

dose any one have the pin out on the c101 connector, that way i can tell which pins go to the ecm

DFlintstone

Wasn't there a show "Car 54, Where are You?" Cruiser54 Where are you?

I bet you need that 5 Volt YELLOW wire connected to the ECM, (does it have 5V?) and there's this:

http://www.bc4x4.com/faqs/yj.cfm?cat=5&faqid=164

cruiser54

No pin-out for the C101. From the ignition switch there is a yellow wire that goes to both the ICM and ECU but does not go through the C101. There is also a yellow wire from the ECU to the ICU for "ignition interference output". It doesn't go through the c101 either.

What goes through the C101 are: TPS, CTS, IAT, CPS, IAC, all injectors.

Have you ever done the actual ground refreshing and C101 refreshing?

Here's what grounds at the G105 ground point aka dipstick tube stud: 2 ECU grounds including the grounds for the TPS, CTS, MAP, IAT and injectors, O2 sensor, Sync sensor, and ICM.

Anything sound familiar or possibly common to your issue??

DFlintstone

I'm curious. Without nailing down all the details and the schematic and all. You say it runs while you have the key turned, and dies when you let off? Could you "back probe" that (3rd), first yellow wire on the ICM with your meter and see what it's getting? Some guys might stick a pin through the insulation, a little iffy but works. Here I would stick a (straightened) paper-clip in alongside the wire/connector.
Maybe a waste of time, but if power drops off there when you let up the key...

Oh...easier, one terminal on the "diagnostic port" is connected there. I found it once with an ohm meter.

AND! We may be running all over for nothing. I once set my kitchen timer, went out and tested my CPS, finished, closed the hood and came back in. Under 3 minutes. They are tricky cridders that seem to be able to do about anything. I'd check mine if my radio didn't work!

DFlintstone

Hey, CK, TJ just posted this, thought you might be interested;

Spark: 12 volts from ignition switch to the ASD relay; when the key is first turned on the PCM provides a ground to the ASD relay to energize it, then the ASD relay passes 12 volts to the coil primary side. If no crank sensor signal is generated after a couple of seconds the PCM cuts the ground to the ASD relay (and fuel pump relay too) and that cuts power to the coil (and fuel pump). Key to START and once again the PCM energizes the ASD relay. Now, a critical element is the crank sensor--no signal from the crank sensor and the PCM won't trigger the coil to provide spark.

My (first yellow wire), remains energized though, (on my 90)

ck88jeep

ok i think i have it fixed. after redoing the c101 , cut it out and soldered all the wires back together , checking all the grounds. buying a part i didnt need, alot of internet time finding out what other people have tried. it ended up being the connections to the fuel pump relay. i put a jumper wire in between terminal 5+6 on the small dia connection and it would stay running. so i tighten up the terminals where the fuel pump plugs into. thank god for the internet. i could not have done it with out

DFlintstone

Hurray! Guess we made a wrong turn in the third sentence, "i check the fuel psi which is 31 psi"! (Suppose it needed to be checked while it was not starting)

Having the C101 ect. cleaned up should ease your ride, and much thanks for getting back.

cruiser54

I haven't done an actual write-up on this but you make a strong point for me doing so. OPh, wait. I just did it!!! I suggest unplugging every connection in the engine bay you can find, spraying it out with a good electronics cleaner, and adding dielectric grease before plugging it back together.

The relays should be removed, the terminals wire-brushed, and the receptacles sprayed out with contact cleaner, then dielectric grease added before plugging them back in.

I do this on every Renix era Jeep I purchase or work on for someone else.

ck88jeep

this is of the topic, but whats the highest lift i can put on without doing a bunch of alterations.

cruiser54

Dude, what are you thinking? You didn't spell OFF correctly!!

James P