Chrysler Repair: 95 Lhs no start, buss lines, abs systems


Question
QUESTION: Hello. we have a 95 lhs and it wont start. there is no check engine light and my snap on scanner will not communicate with the pcm. it will however sync with the bcm tcm and abs systems. i have checked power and grounds at the pcm and triple checked the dl. weve tried another pcm and same problem stayed. any ideas? Thanks

ANSWER: Hi Louis,
Do you mean the check engine light is always dark (burned out or disconnected?) or that it doesn't flash in response to the ignition key routine for doing a fault coder readout? If you have absolutely no light, then either the bulb is out or the data link to the cluster is 'open'. What power have you checked to the cluster? What power have you checker at the pcm? By dl I assume you mean the data link connector, correct?  
Any history to what happened when the no start began?
Do you have spark when cranking it over? Do you hear the fuel pump run when you turn the key to the 'run' position, lasting about a second? If so, can you hear it run when you try the starter motor?
We can try to get fault codes, and then we can forget that and focus on "basics".
Is this a 3.3 or 3.5L engine?
Please 'rate' my answer (see below),
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: Hello. The no start happened spontaneously. it sputtered then wouldnt restart. i checked powers and grounds at the pcm and dl. plus the comm and bus lines at the dl. 0 ohms on the comm to the pcm and 2.6 volts on the buss lines. the check engine lught will quickly flash when turning the key but will not stay lit in ign. plus doesnt flash. my solus wont communicate at all either. but like i said only the pcm. all others are perfect to talk with. autoshut down and feul pump relays will work!!! Its odd....

ANSWER: So when you turn the key to 'run' the check engine light will go 'on' briefly then go dark, correct? And when you do the key 'on-off-on-off-on and leave on' doing that in 5 seconds or less that the check engine light stays 'on' but doesn't flash. or does it not stay 'on' at all?  Have you checked for spark when cranking it?
You say it 'sputtered' and died when trying to start it earlier. I wonder whether, if you do have spark, that you may nonetheless have poor mixture because the egr valve is stuck slightly ajar instead of being closed tight? Check that out and try lubing the stem with WD-40 where it enters the valve body and move the stem with the tip of a screwdriver inserted in the slot of the stem.
These are basics until we can be sure that their are no fault codes.
Please 'rate' my answer.
Thanks,
Roland


---------- FOLLOW-UP ----------

QUESTION: Thanks. there is no spark(no power to the coil). Also no power to the pump or injectors. no check light AT ALL. Only flashes once briefly when turning key from off to acc as you go toward ign. had others try to scan and they cant communicate with system either. ive checked the harness extensively for any wire situations and havent seen anything problematic. has anyone ever seen a prob like this with a chysler? Its got the 3.5L.

Answer
Hi Louis,
Did you check fuses A and B in the power box as they supply the voltage that is put out by the fuel pump and ASD relay. Then try jumping a wire from the rear pin to the front pin of the ASD relay's socket, and similarly at the fuel pump relay socket. That will power the pump and power the coil and the injectors. Then try starting it. This is simply to test, as you wouldn't want to drive it around that way.
Please 'rate' my answer.
Thanks,
Roland