Instrument cluster and related issues

[theWalkinator]

2001 base, the instrument cluster clock adjustment isn't working, thought it was a broken stem so I bought a new pair, remove the cluster and disassembled it, found out that the 2 stems are fine however, the 4 side standing tactile momentary push button micro switches are all corroded, there are rusts on the metal casing of all the 4 switches, I initially dabbed few drops of household vinegar on to the switches, used a tooth brush trying to brush out the rusts on the casing but didn't work, then I sprayed some CRC electric contact cleaner and then put everything back together and put back in the car.

Now the cluster has some odd behavior, the clock adjustment is still not working, however, more serious problem is AC/climate control panel has no power (it is not turning on) and the in the center LCD screen it displays range left rather than trip meter, also, has to make several try to turn on the engine, sometimes need to twist the steering wheel left and right to start the engine.

I then use a scan tool to activate the instrument cluster (OBC I guess?), now the center LCD display is cycling from outside temperature to trip meter to range left and then it stays on range left. I did instrument cluster activation few times and sometimes AC panel is on and working just fine, however, my scan tool cannot connect to climate control module, when AC panel is not powered on, instrument cluster has error code 9115 which is missing AC unit or something like that.

Did I screwed up the instrument cluster? I also think the ignition switch might also has some to do with it, because like I said it won't start the engine, no click, nothing, but few tries it can be started. Another symptom is after pulling out the key, the instrument cluster are still on, lock the door won't make it to turn off, but few minutes later it turns off.

I ordered Deoxit D5 and should be arriving today, I will do another cleaning and will also test those 4 side standing tactile momentary push button micro switches as well as the 2 other tactile momentary push button micro switches that the rock arms activate when push the the 2 instrument cluster stems.

Also checked all fuses, all good, disconnected battery for 20 minutes twice, didn't do any thing.

Any comments on my issue with the instrument cluster and related problems?

[Wret]

The instrument cluster is mostly just a display — it doesn’t directly control engine functions. I’ve personally run my car without the cluster, replaced it, and tinkered with it without any issues starting or driving.

However, in some cases, removing or tampering with the cluster can break part of the CAN bus communication loop. When that happens, it might prevent the immobilizer from properly talking to the DME (engine computer), which can cause a no-start.

[theWalkinator]

Originally Posted by Wret

The instrument cluster is mostly just a display — it doesn’t directly control engine functions. I’ve personally run my car without the cluster, replaced it, and tinkered with it without any issues starting or driving.

However, in some cases, removing or tampering with the cluster can break part of the CAN bus communication loop. When that happens, it might prevent the immobilizer from properly talking to the DME (engine computer), which can cause a no-start.

Yes, scan the code on instrument cluster, got "AC unit is missing" code, also the scanner not be able to communicate with AC control module, aka. Klimatronik. I have just replaced the ignition switch but the AC panel is still not on when turn the key to on position or start engine, have to use the scanner to re-activate the cluster several times to get AC panel to turn on and there is no guarantee that it will turn on next time, so I will pull the cluster and check the 3 plugs to see if any pin is bent, maybe re-clean the 4 micro tact momentary push button switches, but I don't think those 4 switches has anything to do with the AC panel not turning on.

[theWalkinator]

So I replaced the tactile momentary micro switcheand restored the clock adjustment function, however, the instrument cluster is still acting wired, AC panel sometimes comes on and sometimes are not, car sometimes starts and sometimes won't start, have to disconnect and re-connet the connector A (green in my car) to reset the instrument cluster to get car started and/or AC panel on. Originally I thought it is the connector A, so I bought a new set of connectors from Suncoast and de-pinned each pin on connector A, move all pins to the new connector and tested drag on each pin, all seems to be good so I think I can rule out the connector issue.
There are 2 codes, P1601 CAN BUS timed out on instrument cluster and P9115 no AC unit, trying to communicate with AC unit directly but failed, I can clear P1601 code but P9115 AC code is a hard code, cannot be cleared. So I think either the instrument cluster is bad or wire issue on CAN bus, but reset the instrument cluster (disconnect and reconnect the connector A) usually can get car started and maybe AC panel on, but even AC panel is on and AC is working, I still cannot communicate with the AC unit.
Another symptom is after cluster reset and car is running and AC is on, I shut the car off and locked the door, few minutes later the cluster is off, then I try to start the car, no click, AC panel is off, has to do another cluster reset, all fuses are checked fine, what the hell?

[theWalkinator]

Okay so since AC control unit is missing on the CAN bus, I took it out to check, and found out there are only 2 connectors connecting to my AC unit, the large black and red connectors, missing the small black and beige connectors, there are 4 plug wells in the back of the AC unit, and I watched couple of YouTube videos and they all have 4 connectors, mine is installed in the bottom of the center dash so I removed to top CD holders and side panels trying to find the 2 missing connectors, but I cannot find them so mine just uses 2 connectors?

I printed out wire diagram of 2001 Boxster and control unit is labeled as M573, all I see are pins for connector B (red) and D (large black), don't see any pins for connector A (small black) and connector C beige, my AC unit part number is 99665310107.