None of the gauges in my '79 FJ40 (except the speedometer) are currently working. The instrument panel lights do work. I'm sure it's a common issue causing the gauges to not work properly. The fuses appear to good. Any ideas?
'79 FJ40 gauges not working (2 Viewers)
- Thread starter R.K.
- Start date
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JohnnyC
Long ago TLCA# 2231
Amp gauge doesn’t work?
Your multi prong cluster plug may be unplugged ? Had you taken the cluster out to check
Your multi prong cluster plug may be unplugged ? Had you taken the cluster out to check
- Thread starter
- #3
Multi prong cluster plug is connected.
fjc-man
SILVER Star
Yes, inline fuse by battery for the ammeter.
I had to pull the connector off and clean each pin to get things working again on mine. In addition, I found the fuel sender needed repair. Have you tested the senders or gauges individually yet?
fj40ingkc
SILVER Star
Hey checking out where you netted out. I had same issue all of a sudden, where no gauges are working except speedometer. Lights in cluster still work. So there is power. Checked two fuses inline near battery and all fuses in panel with ohm meter and all are working correctly. Any other ideas? I had cluster out a month back to restore it, and after reinstalling all worked flawlessly. Disconnect battery of course when removing cluster. I did install led bulbs in cluster but they are still working and all else worked fine for a month before gauges quit. Been going over wiring diagrams and all seems correct.
fj40ingkc
SILVER Star
I would think if ground was bad for pcb multipin connector, that lights wouldnt work or flutter at minimum. One other bit of info, oil pressure gauge was stuck not working a few days back, then sprang to life half way home. Now all gauges are not working.
I would check pin 3 on your barrel plug. If there is no power to this then all your gauges will go dead. Or maybe it dirty and not connecting to the board. Stick a test light on that pin it should light up with the key on.
If you have power then check your board the leg from pin 3 could be burnt which will result in the same thing.
If you have power then check your board the leg from pin 3 could be burnt which will result in the same thing.
fj40ingkc
SILVER Star
Great picture! Thank you for the info @JVZii , I was going off of my diagram, of wiring harness shown below and will check against yours in AM.
Since mine wasn’t oriented , I checked with volt meter and the ground to turn signal to fine where I was at, and I can see blinking 12V for turn signals. I’ll recheck ignition 12V and ground in morning. I applied 9v little battery to negative and positive of gauges and they came to life individually, so likely not getting power from harness. So I figure its not the gauges as all went out at same time, also I noticed my fans for heater and AC aren’t running. Nice when it’s 10 degrees out!
Since mine wasn’t oriented , I checked with volt meter and the ground to turn signal to fine where I was at, and I can see blinking 12V for turn signals. I’ll recheck ignition 12V and ground in morning. I applied 9v little battery to negative and positive of gauges and they came to life individually, so likely not getting power from harness. So I figure its not the gauges as all went out at same time, also I noticed my fans for heater and AC aren’t running. Nice when it’s 10 degrees out!
fj40ingkc
SILVER Star
So I checked the ignition 12 V and I’m getting nothing with the car key out ACC on or car turned on running. Nothing changes the ground is correct and turn signals are detectable in a barrel connector.. any idea what would cause ignition not to have power at the barrel connector ?
I had a similar issue with my '77 FJ40. It turned out to be the old brittle wires under the dash. I would reach under the dash and jiggle the wires and the lights and gauges come back on.
I think the heater fuse is for the gauges. Are you sure you have 12 volts after that fuse? If you do, I see some wire tracing in your future.
fj40ingkc
SILVER Star
Just checked, and that was the issue…fuse looked good but when checkin with ohms it didn’t beep. Fuse burnt off to a side and looked good through the glass, thank you for the advice.
was going nuts trying to trace it
Post a pic of the restored cluster
fj40ingkc
SILVER Star
@fj40ingkc the cluster looks great.
Hello, I’m having a problem on a ’77 that looks similar. I replaced the bulbs with LED’s and also cut away the little shrouds that go around the two instrument panel lights. The lights all worked when the instrument cluster was reinstalled. When the truck was driven a few days later noticed that oil, fuel, and temp gauges didn’t work. Also, fan motor didn’t work. I took cluster back out and sprayed contact cleaner into the multi-pin connector and brushed the pins on back of cluster. Oil gage and fan motor started working. I checked the heater fuse and it was good. I am getting 12v on terminal A (as described in the Haynes manual). Any ideas what to check next?
Can you get a pic of the board? If the temp and fuel are not working, one of the board leads may have been burned.
See the pic below. That small lead can burn with a quick short. If it is burnt, the fuel and temp gauge will stop working.
