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Schmo
July 16th, 2006, 16:11
99' Cherokee with the NO BUS reading on the Odometer. No gauges work; Check Engine and Airbag Lights on. As per the 8-15-99 TSB I did the swap out on the harness connector. There was only minor oxidation on the male pins.
Hooked up my Autoxray reader and it says no connection to the computer.
Engine cranks but that's all. Would I be wrong to assume that the ECM bit the dust or are there other possibilities???????:explosion

87manche
July 16th, 2006, 17:00
perhaps the ECM just isn't getting power. Check fuses and relays.

CharlesS
July 16th, 2006, 17:33
My 98 XJ has had this TSB done twice by the dealership and once by a local Jeep GURU, but the problem still comes back.
I personally have removed the cluster 4 times to clean the contacts with the same results; the problem reappears within 4-6 months.
On my Jeep when the Airbag indicator illumintes or NO BUS is displayed on the odometer the gauges freeze; I flip the directional selector arm to make a right turn which resets the bus and reenables the gauges.
Not sure what the correlation is..., but it works everytime.

Charles

XJSpencer
July 17th, 2006, 20:23
99' Cherokee with the NO BUS reading on the Odometer. No gauges work; Check Engine and Airbag Lights on. As per the 8-15-99 TSB I did the swap out on the harness connector. There was only minor oxidation on the male pins.
Hooked up my Autoxray reader and it says no connection to the computer.
Engine cranks but that's all. Would I be wrong to assume that the ECM bit the dust or are there other possibilities???????:explosion

If the CPS shorts, it sends the computer into a safe mode where it won't talk to the scanner. Unplug the cps, disconect the battery for awhile, then check the guages and scan tool. If that works, as it did on mine today, replace the cps, clear the code, and fire it back up. I thought my PCM was bad and got a new one. I then figured this out and fixed it and put my old PCM back in. Works great!

edit:
I found it here after I got a code out of the computer.
http://www.naxja.org/forum/showthread.php?t=63167&highlight=p1694

jneary
July 20th, 2006, 19:02
the cps can short out in a way where the check engine light wont even do the bulb check. check to see if it illuminates with the key on. if not disconnect it and see if it comes on then, if so, that is your problem.