Hello all, I am looking for... a place to start and some advice:
- I have a 22 year old car.
- The instrument cluster is only working intermittently.
- There are times when the entire cluster works - and it works with no visible faults.
- When it is not working, there can be several fail modes, including:
- The Tachometer, Speedometer, Odometer do not work at all.
- The Tachometer and speedometer work, but the odometer does not light at all.
- The Tachometer and speedometer work, the background light is on at the odometer, but no digits are displayed.
- There is a suggested fix - removing and replacing bad capacitors. Some say this works for them, so say it does not.
Before I take my cluster apart, it seems I should be able to bench test the unit. I would think that I should be able to remove the cluster to my workbench, attach a power supply and reading the schematics figure out exactly what is and is not working. Q1:
Am I correct?
If the above is correct, I assume, that I should be able to remove the cluster and attach the connector harness to some kind of data acquisition device, start up the car, drive around, download the recorder to my computer, and see (using the bundled software) if I am getting constant voltage to the connectors under the correct conditions?
Further, if all of the above is also true, then can anyone tell me what kind of device I would need to test for voltage/signals to the connectors?
There are 4 connectors at the back of the cluster:
- One 12 pin connector seems to go to the speedometer/odometer
- One 12 pin connector to the tachometer
- One 10 pin connector and one 8 pin connector appear to connect to the Oil Pressure, Fuel level and Temperature Gauges (which all work all the time).
If my suppositions are correct about connecting a data logger, then I am guessing I need an instrument that can handle 12 channels at a time (if I were to test the tach circuit separately from the Odo and Speedo) or 24 channels if I wanted to test them all at the same time.
Looking around the net, I find this instrument...
It looks like the kind of device I need, except for the fact it only supports 4 channels.
Would it be correct to buy 3 of these units and plug them all in at the same time to one of the connectors? Buying 6 for the two connectors seems overkill if I cannot find a 24 channel unit. Q5:
Is there anything more I can learn by recording both connectors instead of one at a time?
Again, I am not versed in any of this, but I am willing to dive in and try - even if I destroy the cluster while learning (I have a backup cluster I took from a dead car).
Any help or suggestions would be appreciated.