Instrument cluster partially working

[bretweir]

Hello all -

I started having problems with my instrument cluster a while back - dimmer switch was intermittent, some cluster lights not working. So I replaced the dimmer and all the bulbs. Some things returned, not all, but the dimmer works fine. One problem down. I pulled it out again, disassembled, cleaned contacts, replaced all bulbs AGAIN with a new (as new as they can be from the jungle website)... and still have things not working. I looked into a surplus cluster, but opted for the remanufacture service with ISS Auto - they do a full rebuild, test etc.

Turns out my cluster is just fine. When I run the gauge test (trip button held when turning key to on) ... all my gauges work. The only indicator that illuminates is the "check gauges" one (ironically)... when the jeep is running, the high beam indicator works, and the right turn signal. No e-brake light.... all others should be normal off anyway. But knowing none of them come on during the test and a couple not working tells me I'm still chasing a problem.

I've done visual inspection of wires that I can see without major disassembly and don't see a smoking gun.

Anyone ever chase this gremlin and find a common problem?

TIA

 

[Chris]

Hello all -

I started having problems with my instrument cluster a while back - dimmer switch was intermittent, some cluster lights not working. So I replaced the dimmer and all the bulbs. Some things returned, not all, but the dimmer works fine. One problem down. I pulled it out again, disassembled, cleaned contacts, replaced all bulbs AGAIN with a new (as new as they can be from the jungle website)... and still have things not working. I looked into a surplus cluster, but opted for the remanufacture service with ISS Auto - they do a full rebuild, test etc.

Turns out my cluster is just fine. When I run the gauge test (trip button held when turning key to on) ... all my gauges work. The only indicator that illuminates is the "check gauges" one (ironically)... when the jeep is running, the high beam indicator works, and the right turn signal. No e-brake light.... all others should be normal off anyway. But knowing none of them come on during the test and a couple not working tells me I'm still chasing a problem.

I've done visual inspection of wires that I can see without major disassembly and don't see a smoking gun.

Anyone ever chase this gremlin and find a common problem?

TIA

Since the gauge test shows that the gauges work properly, it seems like the problem might lie somewhere in the power or ground circuits feeding the cluster. My best guess in cases like this is that there is a short somewhere in the wiring harness and more often than not it can be a real PITA to track down. I had chased a similar problem with the wiring on my old XJ and ended up having to strip down most of the wiring harness behind the dash before I finally found a tiny little break in the wiring that was arcing out on a metal bracket.

A few suggestions:

• Make sure the cluster has a good ground connection. A poor ground can lead to unpredictable behavior. Check the ground wire for corrosion or loose connections.
• Double-check the power supply to the cluster. Use a multimeter to ensure that the correct voltages are present at the appropriate pins while the Jeep is running, particularly for lights and indicators.
• Inspect the connector pins on both the cluster and the wiring harness. Look for any bent, corroded, or damaged pins that might not be making good contact.
• Look for any cracks or damage on the cluster circuit board. Sometimes they can cause intermittent issues.

 

[bretweir]

Since the gauge test shows that the gauges work properly, it seems like the problem might lie somewhere in the power or ground circuits feeding the cluster. My best guess in cases like this is that there is a short somewhere in the wiring harness and more often than not it can be a real PITA to track down. I had chased a similar problem with the wiring on my old XJ and ended up having to strip down most of the wiring harness behind the dash before I finally found a tiny little break in the wiring that was arcing out on a metal bracket.

A few suggestions:

• Make sure the cluster has a good ground connection. A poor ground can lead to unpredictable behavior. Check the ground wire for corrosion or loose connections.
• Double-check the power supply to the cluster. Use a multimeter to ensure that the correct voltages are present at the appropriate pins while the Jeep is running, particularly for lights and indicators.
• Inspect the connector pins on both the cluster and the wiring harness. Look for any bent, corroded, or damaged pins that might not be making good contact.
• Look for any cracks or damage on the cluster circuit board. Sometimes they can cause intermittent issues.

Thanks for the quick reply Chris. I was about to edit my post ... I totally agree with you. Ground is good at the cluster. Checking the individuals when they are supposed to be hot can be a problem, because you have to have the connectors hooked up to do the indicator test.... at least that's what I assume.

One thing I keep looking at is the connectors on my ECU .... because all three have busted clips so I am always checking that they aren't wiggling out.... and only once have have found them slightly out.... but once means it "can" happen. But I digress....

If I didn't live in CA I honestly wouldn't care too much - I can see voltage, oil pressure and temp... everything else is gravy. But in CA, the indicators have to work when I do the damn smog test (coming up in March) or they won't even test it. I know, move out of CA.... working on it.

 

[Chris]

Thanks for the quick reply Chris. I was about to edit my post ... I totally agree with you. Ground is good at the cluster. Checking the individuals when they are supposed to be hot can be a problem, because you have to have the connectors hooked up to do the indicator test.... at least that's what I assume.

One thing I keep looking at is the connectors on my ECU .... because all three have busted clips so I am always checking that they aren't wiggling out.... and only once have have found them slightly out.... but once means it "can" happen. But I digress....

If I didn't live in CA I honestly wouldn't care too much - I can see voltage, oil pressure and temp... everything else is gravy. But in CA, the indicators have to work when I do the damn smog test (coming up in March) or they won't even test it. I know, move out of CA.... working on it.

If the connections on the multimeter (or even a test light) are sharp enough sometimes you can just poke them into the wires to test, that's what I've done.

Of course it's a California thing. Only California would require something so silly.

One thing is for sure, it's definitely an electrical issue and it's almost certainly something to do with the connections. Somewhere in there you've got a iffy connection which isn't at all surprising given the age of these vehicles at this point.

 

[hear]

I've used a back probe kit like this to measure stuff while everything is plugged in and running. I don't love the idea of compromising the insulation, but sometimes it's the only practical way.

https://a.co/d/078oarC8

 

[bretweir]

I've used a back probe kit like this to measure stuff while everything is plugged in and running. I don't love the idea of compromising the insulation, but sometimes it's the only practical way.

https://a.co/d/078oarC8

Thanks... I don't mind poking back there.

 

[hear]

Thanks... I don't mind poking back there.

TJ forum after dark

 

[jonny jeep]

But knowing none of them come on during the test and a couple not working tells me I'm still chasing a problem.

Not all of the lamps come on during the actuator test, only those controlled by the cluster will come on during the test.

The others are directly fed from the relevant circuits. High beam and turn lights are examples of those that are not cluster controlled.

What works during the test depends on model year and in some cases vehicle spec.

 

[bretweir]

If the connections on the multimeter (or even a test light) are sharp enough sometimes you can just poke them into the wires to test, that's what I've done.

Of course it's a California thing. Only California would require something so silly.

One thing is for sure, it's definitely an electrical issue and it's almost certainly something to do with the connections. Somewhere in there you've got a iffy connection which isn't at all surprising given the age of these vehicles at this point.

Thanks again Chris. I'll do that best I can. My brain wonders why there are a chunk of them, not all of them, out at the same time. To me that points to a commonality somewhere up the chain.

Not all of the lamps come on during the actuator test, only those controlled by the cluster will come on during the test.

The others are directly fed from the relevant circuits. High beam and turn lights are examples of those that are not cluster controlled.

What works during the test depends on model year and in some cases vehicle spec.

Good to know, thank you. Is there a reference that you know of for which come on and the "checks" the ECU is running during that test? I've got a 99.

 

[jonny jeep]

There's a section of the FSM that explains what the cluster does. Posting from my mobile though. I think I may be able to post the section from my mobile but it will be a short while.

 

[jonny jeep]

Here the instrument panels section of my 97 FSM. It should be the same regarding how the cluster works.

 

[bretweir]

Here the instrument panels section of my 97 FSM. It should be the same regarding how the cluster works.

Thank you sir!