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Digital dash multiple faulty guages

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Digital dash multiple faulty guages

Old 07-11-2018, 03:30 PM
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Digital dash multiple faulty guages

This one is for those with electrical knowledge. Trying here in case anyone has experienced this before and happens to be able to provide some knowledge.

- most gauges on digital dash go to their mins or maxes readings sometimes
- looks like it is split up between two groups:
one: speedo, trip, torque, and mileage - happens about 70% of the time
two: oil pressure, temp, voltage - happens about 20% of the time, but lately more
- gas gauge is messed up too, after like 20+ miles after full tank, it goes down to half a tank
- tachometer is always fine, temp is usually fine but does mess up sometimes
- recently the entire display started flickering a bit.

- Sometimes when I hit a bump in the road, it will cause it to faulter.
- While driving, to stop the flickering, I can push on the top right of the display with my finger and it stops flickering and everything goes back to normal readings. To me that would indicate a loose wire or connection! Maybe pressing on it stops vibrations in the cluster because it doesn't seem I need much pressure at all. I'm thinking something is vibrating enough to loose connection with it's contact.
- It doesn't appear temperature is a factor, but might be a factor in the flickering (not enough testing yet).

What I've done:
- Did a thorough troubleshooting with the manual, checking voltages, resistance, continuity, etc. and all checked out ok.
- Opened up the dash case/cluster and checked all components and their solder joints.
- No bad solder joints.
- Two capacitors had very minor corrosion. Cleaned them up.
- Two components that are white rectangles with electronics on them, were bent sideways some, which looks like it came from from hitting a huge bump and hitting the casing.
- Some pins were bent over, pins for the actual display, which I bent back
- Small corrosion around a diode, but can't get to it because of some casing around the pins.
- Did continuity check on wires from cluster to power unit. Looks like one group of gauges go to one microcomputer, then the other ones go to the other microcomputer. Then both microcomputers go to the power unit. Common factor, the connection between the control unit. I checked continuity all the way from the board on the power unit all the way to the exiting wires from the cluster to the physical sensors, so no continuity issues across the board that I could find. I haven't done voltage checks though, it's too hot to sit in my car and do that with it all plugged in and I don't have an external power source right now.
- I re-soldered the power unit pins as suggested by other forum posts and videos, suggested for when the display goes out. Re-solder did nothing.
- When this first started, it was only the speedo group, and I changed out the speedo cable because it looked like **** and was leaking fluid all along it. It didn't fix the issue.
- scoured forums for any help on this, but most talked about non-similar issues. One was similar, but no answers provided and no conclusion from the poster. I may try to contact them.

Possible conclusions:
- This seems more likely caused by vibration to some component or wire, most likely a short in one of the wires for power due to the screen flicker.
- Maybe a wire is getting pinched and with vibrations or bumps the internal wire partially separates. If that's the case, I'm likely out of luck finding this!
- Some bad solder join somewhere. I checked them all thoroughly so I'm not thinking so
- The white rectangle component lodges against the outer casing, and is connected by many prongs that simply hold it in place, and looks like I could potentially just pull the whole thing out almost like a plug. But I don't know what that is so I'm not doing it. When I press against it, it moves loosely. Not enough to say that's gotta be it, but looser than the other two white rectangle components. See picture.

Also, I may just have to find a working power unit and swap it out, or a another dash. Anyone have any available?

Your thoughts?
If you don't know, please don't just respond "looks like you need a new digital dash," because it's quite obvious that might be where it's heading. I'm looking for someone knowledgeable in this stuff, in case it might be able to be saved. I may let a friend with an electrical engineering degree and profession have a look, or ask him about this write-up, but thought I would try here first just because I know the digital dashes have issues over time and probably enough people here have had to deal with them and maybe shed some light. I have a mechanical engineering degree, so I have some knowledge and have fixed electronics, mostly computers, but my knowledge is a bit limited and have gone through the gambit of what I can and do know.


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