[ajchien]

2003 Element EX 2WD side airbags.

Gauge cluster backlights, HVAC lights, AT shifter light, cruise main light, emergency flasher light are out and not working.

So UHFB Fuse 2 and UDFB fuse 10 are good. G502 is also good.

Backprobing instrument cluster gauge pins A14 and A11 show good solid power, and A15 and A30 good ground.

A16 when backprobed has inconsistent ground signal and measures 1V on the meter. When connector A is unplugged, it’s got solid battery power on the red A16 wire.

Id like to make the call of a bad gauge cluster, but I’m not sure what the voltage regulator, capacitor, and variable transistor are doing to my measurements at A16.

If you guys have any idea what I’m talking about, I’ll appreciate any help.

 

[07lmnt]

The red wire is the ground side. The voltage regulator is supplying a variable ground dependent on dimmer position. I would cut the red wire near the cluster and using a 12v incandescent test light connected to battery+ it should light and dim. If not the cluster is the problem.

Cold solder joints are a known cluster problem.

 

[ajchien]

@07lmnt Thanks for the help. I apologize, as the results I currently have is not as satisfying as I wanted it to be.

It turns out that I have “accidentally fixed it” after manipulating it. As in, everything currently works. Intermittent strikes again.

When I was previously checking for power and ground, I was using a powerprobe rather than an incandescent test light. My incandescent test light draws 250mA, while my PP draws 15mA, so I had chosen the PP bc I thought it was going to be “safer” for the cluster cpu (theoretical risk only?). When I had probed A16, the PP gave me an alternating power/ground beep, which is why I took out a meter and got 1V. Now with it being “self fixed”, the PP still alternates the power/ground beep, but a meter is measuring 10-12mV. As before, I don’t know what the volt reading really means given the capacitor/transistor-dimming circuitry in there. Dimming currently works fine.

The E is the wife’s vehicle. She currently tells me not to touch it anymore unless it “breaks again”. I’ve got better things to do other than to argue with the wife today. Im sure it will happen again, I’ll have the incandescent test light out then.

I think I missed another opportunity. When I had A16 unplugged i could have provided a good ground to the red wire, to see if that would have lit up the HVAC etc lights.

I am aware of cold solder joints at the connectors in Es. I’d just rather prove it to myself before opening it up. My re-soldering skills of circuit boards are functional, but they are ugly and I’m never happy with the appearance. I should probably just send the cluster out to someone.

 

[07lmnt]

Experience has me not trusting those power probes thingys. Lead you right down the rabbit hole.
A 12v test light still has it's place in modern cars, it will load the circuit slightly. A DVOM will not load a circuit and can fool you into false results too.
10-12mv on the ground side is a small amount of voltage drop in the circuit, should not be enough to make the lites inop.
When it acts up again , ground the red wire. If the lites work, it's a problem in the cluster.

 

[Chop_E]

I think 07lmnt is on the money, as usual. It may be worth noting that I just had the cluster on Chop_E repaired by Module_Master on ebay and it fixed the issue I was having. They list backlighting problems as one of the common repairs they do on E clusters. If it comes down to a faulty cluster that may be an option that’s worth exploring.