QuestionQUESTION: I have a 1999 LHS with an instrument cluster problem. First the air bag light comes on, next the fuel light and than the other warning lights. The speedometer and Tack are the last to go followed by the no buS in the odometer window. I have been doing some reading and several things are in common with others having the same problem. 1- The battery was just changed and 2 - Water got in the drivers window. When I changed the battery I needed to use a new and not as thick negative ground cable. It appears to be a ground problem. Could the new cable be the cause. The problem is intermittent and worse in very cold weather. I have tried the usual hitting and shacking – no effect. I removed the instrument cluster and it looked OK. When I hold in the trip reset bottom and turn the ignition on the cluster goes through a set test but no code. - Roger
ANSWER: Hi Roger,
There are several possibilities I see that might be worth looking into. I don't believe the new battery or the size of the return cable is involved. I would be either begin by removing the junction block(fuse box) and bcm combined module from the instrument panel or inspecting the condition of the plug socket of the cluster where they connect to the circuit board.
To remove the junction block/bcm:
Disconnect the battery, then remove the left end cap from the dash. Then remove the 2 screws from lower instrument panel cover (Outside end); then pull rearward on the cover, releasing the clips. Disconnect decklid release wiring, then remove the panel cover.
Remove wire harness connectors for the junction block/bcm
Remove the module's three mounting screws.
Remove module by pulling down from the bayonet mounting bracket.
Remove the wire connectors and remote keyless antenna connector from the module. Remove module from the vehicle.
Then remove the 4 screws that hold the junction block and bcm together and separate the two parts.
Once you have them apart inspect the interconnection face for water/debris and inspect the sockets of both for water/debris. Also check all the plugs, similarly. I would suggest getting some electronic circuit cleaner from an electronic store and spraying all these possible sight for water having intruded and thus causing the various 'gremlins' that you are now experiencing. When the cleaner evaporates it also evaporates the water residue where it has been in contact.
Then put it back together and see if it has correced things.
If not, then I would remove the cluster and inspect the connection between the cluster circuit board and each of the pins of the 2 plug sockets. Those solder joints are known to fatigue which will also cause gremlins and "no CCD bus" on the odo. In fact, you might want to do this before taking out the junction block/bcm. Use a soldering pencil to reheat all the pin/circuit board solder joints to assure no open or flaky connections.
I think you will find that it is either water intrusion or a cold solder joint on the cluster that is causing your problem.
Roland
PS May I ask a favor? If you would use the 'thank/rate' tab below you will find a question about a nomination of the me to be 'expert of the month'. If you believe this answer has been helpful, I would appreciate a 'yes' in response to that question. Thanks in advance.
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QUESTION: Roland - Is it a coincidence that the air bag is always the first warning light to come on and the last one to go off. Also, should I use the dielectric grease when putting back together.- Roger
ANSWER: Hi Roger,
I suspect it has to do with the priority of order of the data sent on the bus, but that is a guess. I hadn't thought of whether to use dielectric grease on contacts in the cabin. I am uncertain about its benefit or its downside for low voltages. If you have experienced contact problems due to local climate conditions then I would consider using it. I hope you are successful in this project.
Roland
PS Thanks for the evaluation and nomination.
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QUESTION: Roland - I did all the things you suggested and instead of the problem being intermittent, it now occurs all the time. Any other suggestions. I did not see any water intrusion or bad solder joints. - Roger
AnswerHi Roger,
How are things going with the instrument cluster? Please feel free to use the "thank/rate" tab to get back with progress/questions.
I'm only 2 votes short of catching up to the fellow who leads the race to be 'expert of the month'. So if you would take a moment to use the "thank/rate" tab below to give me another vote, that too would be much appreciated. Best wishes for the New Year.
Roland
HISTORY
Hi Roger,
If you haven't already done the bcm/junction box interface and the plugs of same, using spray electrical contact cleaner I would be inclined to do that. If you have an ohmmeter did you verify the pin to circuit board was patent for each pin of the cluster socket would be the only other suggestion. Also how about a free readout for fault codes at an Autozone parts store to see if that might help us to focus. Ask for the 4-digit fault code numbers. An independent shop will charge under $40 for such readout. Check fuses 1 and 7 in the junction box under the dash, also.
Roland
Thanks for the nomination, feel free to do it again!
