vipernicus42

iTrader: (4)

Hey Guys,

I'm troubleshooting some Instrument Console issues left over from a big electrical short that happened last year and I'm trying to get all the warning lights working before I bolt the whole console back together.

I vaguely remember that some lights come on when the car is in accessory mode, but I think others come on only when you first start the car or something?

Here's what I've got lit up when I put the ignition into Accessory mode but not started, does this match yours?

Status, in order:
- Rear Defrost - WORKS! (Only if switch on)
- O/D - Not Applicable
- Add Coolant - Doesn't Work
- Brake - WORKS!
- Stop Lamp - Doesn't Work
- Washer - Doesn't Work
- Battery - Doesn't Work
- Oil Level - Doesn't Work
- Low Fuel - WORKS!
- Exhaust Gas Overheat - Doesn't Work
- Seatbelt - WORKS!
- High Beams - WORKS! (only if high beams are actually on)

I found a picture of someone's console lit up like a Christmas Tree and I'm wondering at what point that happens:


​​​Cheers,

Jon

KansasCityREPU

iTrader: (9)

I believe the image position is IG.

Key positions are:

OFF
ACC
IG
START

vipernicus42

iTrader: (4)

I just went out to check because I was like "No way, it can't be that simple!"... Spoiler: It wasn't. But I did learn something.

Turns out that the detent on my "Accessory" setting is so worn down that what I thought was "Accessory" is actually "Ignition". If I very slowly turn the key from the off position I do hit a spot where my aftermarket stereo lights up but my Instrument cluster doesn't. That must actually be ACC. Then I keep going and get to the point where I get those three lights on my cluster, and a hard stop. If I push past the hard stop it turns the car over.

So yeah, my title should say "In IGN" not "In ACC".

But what I'm understanding is that everyone else gets the whole bloody row of lights in IGN, and I only get Brake, Low Fuel, and Seatbelt... ****.

KansasCityREPU

iTrader: (9)

Have you checked to ensure the bulbs are not blown out? The factory service manual has a test for the overheat light where you short the connector. The overheat sensor is on the passenger side between the console and seat. You have to take the seta out ands pull the rear half of the carpet back. That is where the connector is. Then unplug it and short the the pins. The dash indicator for overheat should light up. Taking the cluster out is a PIA. I have mine torn apart right now also.

My ignition switch ACC is also a little tricky to get to. It's just a slight turn. I've been putting a new radio in and testing with ACC.

vipernicus42

iTrader: (4)

Its definitely not the bulbs themselves. When I knew that the console would have to come out to swap the blown tachometer (from the surge last year) I went and bought brand new bulbs for the whole thing.

At first I bought regular #74 bulbs from RockAuto - note from the wise : don't buy the 74LL "long life" bulbs, the body of the bulb is ever so slightly wider so they bend the sides of the bulb holder out and make them nearly impossible to insert back into the holes.

Anyway, I forced those bulbs in and they gave the above result. So then I went and found some LED replacements, but of course LEDs are unidirectional. After messing with directionality for the LEDs for a bit I wasn't further ahead so I decided to put them aside and just use the bulbs out of the two consoles I had (my original one and the one I bought to salvage a replacement tach from.

No dice. Same lights.

To make sure it wasn't a problem with the console itself, I swapped everything over to the replacement console that I swapped the tach out of. Same result.

So the problem is elsewhere in the electrical system.

I swapped in one of my spare choke/check relays (I blew through two at one point due to a shorted wire so I have a stockpile of 3-4 extras). No change.

​​​​​The last thing I did last night was that I also swapped the ECU in the passenger's foot well since I bought one after the power surge but hadn't installed it yet. Nothing.

​​​​​I think I might start going through the FSM procedures for testing each light, like the instructions you gave for the Exhaust Gas Overheat (a sensor that I removed years ago so that's one light I didn't expect to work). It should be pretty easy to test Low Coolant, Low Oil, and Stop Light by unplugging the sensors and shorting them, but I think I can't do that in IGN mode because in that mode aren't they all supposed to light up, even if your oil/coolant/fuel isn't low?

vipernicus42

iTrader: (4)

I broke out the multimeter and tried out all the pins in the round connectors to see what I'd get: I'm going to re-test later with the battery hooked to the charger because I think it was slowly dying as I got further along in testing.

---Connector C-02---
BR - Brake - 12.19v
- BR grounds out, connect other multimeter probe to 12v
- Works on IGN

YB - Coolant - 11.25v
- YB carries 12v, connect other multimeter probe to ground
- Doesn't work on IGN

GW - Overdrive - Skip

GY - Overdrive - Skip

LG - Rear Defroster - 12.20v when switch ON
- LG carries 12v, connect other multimeter probe to ground
- Works when switch ON

GR - Left Turn Signal - voltage present on turn signal switch or hazards but changes too fast for multimeter to keep up.
- Interestingly, has the same blink speed issues I'm seeing when the while thing is assembled (blinks super fast if I use the turn signals via the combo switch but blinks normal speed if I use the hazards) so we can eliminate the cluster as the issue. Carries 12v, connect other multimeter probe to ground.

GO - Right Turn Signal - same as Left turn signal.
- Super fast on combo switch, normal speed on hazards.
- Carries 12v, connect other multimeter probe to ground.

B - illumination ground
and
RL - illumination positive
- When headlight stalk is turned to "illuminate" and the dimmer is at full, carries only 10.73v. Something on positive side of circuit must be dragging voltage down as changing the ground source does not help.

YG - Tachometer - won't indicate without car running but was working when the console was installed for the test run after installing the new (to me) tach.

---Connector C-01---
YW - Temp Gauge - 11.91v
- Grounds out, connect other multimeter probe to 12v

Y - fuel gauge - 11.91v
- Grounds out, connect other multimeter probe to 12v
- Works on ACC

RL - high beam - 10.94v when high beams on
- Carries 12v connect other multimeter probe to ground.
- Works when High Beams ON

B - ground - 11.91v (thats what the batt is down to at this point)
- Is literally ground, so obviously the other multimeter probe connects to 12v

BR - Speed sensor - 5.58v??
- Carries voltage, not sure if 6v is correct?!, connect other multimeter probe to ground. What does this even do, is there a light this is associated with?

GB - Seat Belt - 11.57v for a while upon IGN mode at first, then goes out (by design).
- Grounds out, connect other multimeter probe to 12v.
- Works on IGN

RB - Exhaust Heat Hazard
- Manual says this should be RY for 12a, RG for 13b but mine is RB?
- No Voltage regardless of where I connect the other end but I removed the senaor years ago.
- Doesn't work on IGN

YB - Low Fuel - 11.90v
- Grounds out, connect other multimeter probe to 12v
- Works on IGN

YR - Oil level low - 10.98v
- Carries 12v, connect other multimeter probe to ground
- Doesn't work on IGN

YL - Generator/Alternator - 10.68v
- Carries 12v, connect other multimeter probe to ground
- Is this the voltage gauge? If so this works on IGN. There doesn't seem to be a light for it unless that's the battery light.

LB - Washer Fluid Low - No voltage no matter what I do, but that sensor is also currently removed.

vipernicus42

iTrader: (4)

Well, I made one small discovery.

I grabbed the FSM and started going through the section on testing the console lights (Section 15, Body Electrical, page 15-24, "Warning Lights and Sender Units). I wasn't having much luck until I got to " Alternator Warning Light" (which actually is the picture of a battery, so that answers that question I had...).

I unplugged the 4-pin connector from the choke/check relay and jumped the Yellow/Blue wire to chassis ground, and then this happened:



That's my actual console (unlike the pic in my first post that I found somewhere at random). And basically now I have everything but Low Coolant and Exhaust Overheat!

So either all the choke/check relays I have are bad, or from experience I may have blown an alternator again.

I ran out of troubleshooting time for the night so I'll have to pick it back up later. I suspect that the Low Coolant one is a blown "Coolant Level Sensor Unit" - not the sensor itself but a small device with 6 pins under the dash. It wouldn't be the first thing under there that I had to replace since the surge. As for the Exhaust Overheat, I disconnected the sensor years ago. But then again I did the same for the Washer Fluid Low sensor and it lights up so more investigation is required.

Cheers,

Jon
​​​​​

KansasCityREPU

iTrader: (9)

Nice work. Another thought, since you grounded that wire, I wonder if your missing a common ground and by grounding that connector it back feeded the needed ground to the other circuits.

Frogman

Semi on topic , all of my lights only work when its warm out as does my clock, if its cold my coolant light doesn't work 😂🤣

vipernicus42

iTrader: (4)

These cars are getting up there in terms of age. So am I. So I sympathise with how the car feels when it doesn't want to work quite right sometimes.

But unlike with people, I'm planning on re-doing the whole wiring harness at some point soon. Just need the time and space to make it happen!

Frogman

I feel they develop a sort of personality , just odd characteristics we can't fully explain until we replace the whole thing.