QuestionQUESTION: 95 New Yorker.The gauges and heater/ac went out suddenly.No speedo and no blower on heat/ac.Checked fuses,they all look fine.I hate electrical issues!Please try to point me in the right direction.Thanks
ANSWER: Hi Paul,
On the heater/ac: is this a conventional or an automatic temperature type of control panel? Also, is the fan working on 'high' speed or not at all? Anything else apparently not functioning on that panel?
On the speedo, are all the other gauges 'out' or just the speedo, and is theodometer also out?
Roland
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QUESTION: Thanks for the quick reply;The ac/heat has the auto type control,the fan does not work at all and the odmeter is non functional. Almost forgot,the gas gauge doesnt work and I believe the temp is gone as well.
ANSWER: Hi Paul,
I looked for a common power source cause, but couldn't find anything on the + side. You might want to trace one of black ground wires to its location under the dash at the midline of the body on what the wiring diagram calls the 'ASDM bracket' (which grounds the cluster, the airbag module, the cruise control, and heater/ac control panel) as a loose connection there can take 'out' several modules.
Otherwise, my suspicion is that the digital data bus, center in the body control module, is not functioning as that is needed for both the cluster gauges and the ATC control to communicate. It is powered by fuse #17 behind the left end-cap of the dash, and which in turn is powered by the ignition switch from one specific section that only powers that fuse. So look closely at that fuse to see if it might have a subtle crack in it, and also check that it shows 12v to be present when the ignition is in the 'run' position as the switch could be at fault.
Roland
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QUESTION: Replaced#17 with new fuse,still dead.There is power to circuit as lights on ac/heat control panel are operational.What is location of digital data bus, center in the body control module?Also how would I check to see if it is at fault?Also you mention the ignition switch"also check that it shows 12v to be present when the ignition is in the 'run' position as the switch could be at fault". Again how would I check that to be sure?
.
AnswerHi Paul,
Checking for voltage on #17 as I described will verify the ignition switch I was concerned over. There is one other section of the ignition switch that would cause the symptoms. There is another fuse, #14 behind the dash, that powers the body computer so verify it the same as you have (and will for voltage in 'run') fuse #17.
The body computer is located behind the trim panel and cloth panel behind that at the right side cowl (to the right of the passenger's right lower leg). It is possible that if you were in a heavy rain/car wash when this began that water dripped down througn the edge of the windshield on the three multi-pin plugs that are on top of the bcm. So if the fuses work out to be ok and powered, then you can get to the bcm by removing the right end-cap of the dash, the trim panel of the cowl, and cut through to cloth. Then spray some electronic circuit board cleaner on the plug/socket interfaces that would evaporate any water contamination that might be shorting out the signals. The malfunction of that unit would be to use the ignition key:" on-off-on-off-on and leave on" doing that in 5 seconds or less elapsed time. Then watch the check engine light to see it begin to flash, pause, flash, etc. Count the number of flashes, then repeat to be sure of an accurate count. Then group the counts in pairs in the order of appearnce to form the two digit fault codes. A 66 code would implicate the body computer data bus wire communications as not carrying digital signals as they should.
Roland
PS Please 'rate' my answer. Thanks
