Skip to main content
Topic: No dash illumination (and I think i looked at everything) (Read 4738 times) previous topic - next topic

No dash illumination (and I think i looked at everything)

All of this happened when I re-upholstered my dashboard/new heater core and reinstalled everything. Here's the problem:

Number 13 and 18 fuses blew, I fixed it by removing the Systems Sentry thing in the dashboard.  The copper lines on the SS's printed circuit were touching each other. 

But I still don't have dash lights.

Looking at the EVTM i checked fuse 4 (it's fine) and the cluster illumunation relay.  I switched the relay with the same one from the auto headlights and nothing changed.  I wiggled the hell outta the dimmer wheel and nothing.  I changed two headlight switches and nothing.

I am completely stumped, aside from maybe that the SS module needs to be installed to complete the circuit?  Is that even possible?
pro-five-oh

88 Cougar XR-7...5.0HO, T-56, and much more                             
85 Thunderbird 30th...#2471, 29k, all original and might actually stay that way

No dash illumination (and I think i looked at everything)

Reply #1
Update: got another Systems Sentry module from a parts car and it blew the fuse again.  I'll have to look around the dash to see if its wiring is at fault, but I can't see anything odd yet.
pro-five-oh

88 Cougar XR-7...5.0HO, T-56, and much more                             
85 Thunderbird 30th...#2471, 29k, all original and might actually stay that way

No dash illumination (and I think i looked at everything)

Reply #2
Do you have some multimeter? Does it blow the fuse if the SS module  is disconnected?

Fuse nr. 13 - 5A - instrument cluster illumination lamps, radio, climate control
Fuse nr. 18 - 10A - warning indicator lamps, throttle solenoid positioner, low fuel module, dual timer chime, tachometer, washer fluid level indicator

So if both fuses are blown simultaneously, try to disconect the instrument cluster. It's only thing connected to both fuses I think.

No dash illumination (and I think i looked at everything)

Reply #3
Yeah it doesn't blow fuses with the SS disconnected.  The gauge cluster works now, the tach died when both fuses blew. The SS is just in the dash, not connected.

I have a multimeter, not sure what to check because the shop manual isn't clear on that.

I might just buy another relay, not sure what else it is.

The stereo is working fine, I know that is a problem spot when installing an aftermarket unit, but I had functional lights when I did that.  No pinched wires there.
pro-five-oh

88 Cougar XR-7...5.0HO, T-56, and much more                             
85 Thunderbird 30th...#2471, 29k, all original and might actually stay that way


No dash illumination (and I think i looked at everything)

Reply #5
Whoops sorry about that. It's my 88 Cougar XR-7.

I'm burnt out on the car right now, but I'll take a multimeter to a light socket, the relay and the fuse to see just how far the current goes in this circuit. What really burns me is that it worked FINE when I installed the dash, but by the time I installed everything into the dash, it went out! :mad:
pro-five-oh

88 Cougar XR-7...5.0HO, T-56, and much more                             
85 Thunderbird 30th...#2471, 29k, all original and might actually stay that way

No dash illumination (and I think i looked at everything)

Reply #6
What relay are you speeking about? About IC illumination relay, or about another one? I really don't know, why your tacho died. There must be some another fault in the circuit.

No dash illumination (and I think i looked at everything)

Reply #7
Yeah, the IC illumination relay.

The tach died because of the fuse blowing, which doesn't happen anymore because the Systems Sentry isn't connected anymore. That problem is fixed.
pro-five-oh

88 Cougar XR-7...5.0HO, T-56, and much more                             
85 Thunderbird 30th...#2471, 29k, all original and might actually stay that way

No dash illumination (and I think i looked at everything)

Reply #8
Quote from: pro-five-oh;300247
Yeah, the IC illumination relay.

The tach died because of the fuse blowing, which doesn't happen anymore because the Systems Sentry isn't connected anymore. That problem is fixed.


What is Systems Sentry? Is this unique to 88's ?

No dash illumination (and I think i looked at everything)

Reply #9
Systems Sentry is an informational panel located under the radio. It is an extra equipment, but I think most Birds have it. It has 6 bulbs - door ajar, low beam out, rear lamp out, low washer fluid, low fuel and low oil.
You can find the same SS in 83-88 Birds/Cougars (birds definately).

I'm not sure with this, but cars equiped with standard semi digital IC have some indicators directly on the IC.


No dash illumination (and I think i looked at everything)

Reply #10
Quote from: Trinom;300472
Systems Sentry is an informational panel located under the radio. It is an extra equipment, but I think most Birds have it. It has 6 bulbs - door ajar, low beam out, rear lamp out, low washer fluid, low fuel and low oil.
You can find the same SS in 83-88 Birds/Cougars (birds definately).

I'm not sure with this, but cars equiped with standard semi digital IC have some indicators directly on the IC.

Thanks. The term "System Sentry" is not used in the EVTM. These were optional on the 84 T-Bird and mine does not have them. The Owners Guide calls them "Diagnostic Warning Lights"

No dash illumination (and I think i looked at everything)

Reply #11
I know. Some 87-88  (and maybe 85-86) has an ash tray at the place where should be the SS module located. Please ask some other expert :D.
I have my '86 and few pieces from wrecked 87/88 and I don't know exactly all the details of other model years. I'm still learning too :mullet:. The previous photo is from my '86. 87/88 (I don't know exactly, what part is from silver '87 and what from black '88, so I will use this marking) was V6 with base cluster and it didn't have SS, but there were some indicators in the IC. I don't have the base cluster at home, so I can't tell you the details now.

PS: I didn't wreck it, but I had an offer to buy some rests from these cars very cheaply.

No dash illumination (and I think i looked at everything)

Reply #12
The full digital dash has all of the same lights in it.

I am having my guage/RPM light randomly going out and coming back on. I am thinking it is probably the curcuit board behind the dash clusters.
Quote from: jcassity
I honestly dont think you could exceed the cost of a new car buy installing new *stock* parts everywhere in your coug our tbird. Its just plain impossible. You could revamp the entire drivetrain/engine/suspenstion and still come out ahead.
Hooligans! 
1988 Crown Vic wagon. 120K California car. Wifes grocery getter. (junked)
1987 Ford Thunderbird LX. 5.0. s.o., sn-95 t-5 and an f-150 clutch. Driven daily and going strong.
1986 cougar.
lilsammywasapunkrocker@yahoo.com

 

No dash illumination (and I think i looked at everything)

Reply #13
Jeeves, have you had any opportunities to look into this further?

If not (or even if so) I have some homework for you...

- Leave the System Sentry unhooked. You've got to have a pinched wire somewhere in that system (or metal is touching a wire), but for the time being it seems unrelated to your instrument cluster problem.

- With the headlamp switch on, do you have illumination in the clock? How about the radio?

- Does the light in the ashtray in the console light up with the headlamp switch?

- Now, does everything light up BUT the cluster? It's the only problem in the whole illumination system when the switch is on?

- Pull the System Sentry from the dash, dig out the harness and find the wire that is light blue/red. I'm going to ASSume you have a test light. When you turn on the lights from the headlamp switch, does your test light on that wire light up?

I'm just trying to isolate the problem here, that's all. I've had a little bit of experience with this. ;)

No dash illumination (and I think i looked at everything)

Reply #14
i just havent had time to look into it,  I figured the problem would be easy to find since everything worked prior to all the work done.  i figured in a couple days the pinched power wire on some secondary circuit of the system would have been found.