'99 Jeep wont start: HELP

[toast]

First on any 96-up XJ or 97-06 TJ if the CPS shorts out internally it will pull the PCM down thereby making the gauges not work, you can't talk to the PCM with a scan tool, and most importantly the fuel pump will not turn on for a few seconds when the key is just turned on to prime the fuel rail.

Special note. Do not just swap engine controllers without knowing one very important thing. You can not swap if one has the factory SKIM (sentry key) or VTSS )theft alarm) and the other does not. As long as both part #'s are the same and both equipped the same (with ot without alarm/sentry key) then it should be safe to test by swapping.

Good piont, dont have to worry about the keyless entry thing on TJ's...

 

[MJR]

Good piont, dont have to worry about the keyless entry thing on TJ's...

But some later TJ's have the Sentry key system (gray key with the chip in it).

 

[HMGanja]

Just to put some closure on this thread (and help anyone it can), it was in fact the crank sensor. Replaced=FIXED Have a good day.

 

[bill99]

Hi, first post from uk new guy here, this thread helped me a lot, I had similar symptoms on my XJ, a 99 Orvis 4.0ltr, and I have been on a steep learning curve reading all over the place. In my case the instrument panel meters were all showing low or no readings and the airbag light was on as well.

I set about ordering a CPS but before I got to that stage I noticed another thread here about the connector causing the problem, so what the hell un-plug and plug in again and it started right up.

Seems to me like it must be an open circuit condition and it just upsets the logic in the computer module. Makes me wonder how many CPS sensors have been changed out and appeared to be faulty when in fact it was just the connector.

Cheers

Bill

 

[renomn1]

Nice