[kryptronic]

Hello, all. New member here from York, PA with an 81 TTA I'm trying to work through some issues with to get all systems working prior to a full restore.

I just pulled a non-working aftermarket radio from the dash and found everything hacked up behind it.

I was able to isolate the 12 factory radio wires, but have a cut bundle of 7 wires that I can't identify. I've checked all through the FSM and body manual and can't find a reference to these in any of the schematics. Pic:



It's the bunch right in the middle. 7 wires - 1 green, 1 yellow, 1 faded orange or faded pink, 4 white. To add, I'm pretty certain everything in the dash works fine except the the fuel gauge, but I believe that's the sender.

Any pointers are appreciated. Once I figure this out I might have a question or two on disconnected connectors back there, too. Thank you.

[johnta1]

Does the engine run?


I don't have any good diagrams, but I wonder if some may be for a seat buzzer? Also, does the turbo gauge/light work?

[P@blo]

I will take a crack at this. The only place I see a four white wire tie-in is for the door switches. Take a look at the diagram to compare.

Tan: ignition swith
Yellow: directional signal hazard connector
Green: backup lamp switch
White 1: headlamp
White 2: door courtesy lamps
White 3: LH door switch
White 4: RH door switch
(source is the Fisher body connector)

[kryptronic]

Originally Posted by johnta1

Does the engine run?


I don't have any good diagrams, but I wonder if some may be for a seat buzzer? Also, does the turbo gauge/light work?

Thanks for that. Yes, the car runs, but not well. I need to send the carb out to TTA Performance for rebuild. It was rebuilt before I got it and it's not done right. It fails to idle correctly and wants to die in closed loop, and once the computer takes over it starts running better but still not right.

I haven't had the turbo kick in yet as it's not running well enough ahead of the turbo to spool it up. I'm learning about the turbo.

I did the usual to it - tune up and plugs. I have the cap, rotor and wires and just need to find time to put them on. Found the cat was clogged so I cut that out and I'm just running open at the downpipe at the moment while I get the rear exhaust hung right.

I was getting a CEL in open loop intermittently and that's gone away. I either disconnected something when pulling the radio, the bulb died, or the computer is happier at the moment. Pulling the plugs for the MAP and Baro sensors don't throw a CEL so I'm thinking the bulb is burnt out.

It's got small issues all over. On top of all of it I am pretty sure it's burning old gas mixed with new gas and none of it is any more than 87 octane.

The turbo light switch on an 81 is near the console, not in the dash. Turbo lights work. At least low brightness in normal (no boost) mode works. I haven't seen the others light up and have to address that at some point, but I need to get the carb rebuilt, ensure the turbo is working, then I'll worry about those if they don't light.

The long-winded answer is that I'm pretty sure everything is working in the dash at the moment except the fuel gauge and I believe that's the sender. I think this mystery bundle of wires is from an unused connector and whoever "installed" the aftermarket radio cut it and didn't use anything from it.

[kryptronic]

Originally Posted by P@blo

I will take a crack at this. The only place I see a four white wire tie-in is for the door switches. Take a look at the diagram to compare.

Tan: ignition swith
Yellow: directional signal hazard connector
Green: backup lamp switch
White 1: headlamp
White 2: door courtesy lamps
White 3: LH door switch
White 4: RH door switch
(source is the Fisher body connector)

Thank you. This is promising. The screenshot you posted of the body harness was low res and I couldn't make out everything on it. Where did that diagram come from? I'm asking because my 1981 Pontiac FSM has a different diagram.

The 1981 FSM shows for the F-series shows that body connector as an 11 pin connector with 7 wires (which matches your diagram) but the wire colors are different. They are:

156 White (From White Bundle)
340 Orange (Fused Turn/Backup/Courtesy/Clock)
30 Pink (Printed Circuit Telltale Connection)
24 Lt Green (Back Up Light Switch)
9 Brown (Bulkhead Connector)
19 Dk Green (Steering Column Connector)
18 Yellow (Steering Column Connector)

I don't have electric door locks or windows so would that mean the body harness won't be in the car and connected to the missing connector? Maybe I'm just confused.