83 T/A CCC LG4 Auto

1 green wire. Connected to harness coming from driver's side along with wire that connects to sensor on firewall. Next to brake booster.


2 wire plug. Forgot what color the wires are. Could be green and black. It's part of one of the T-block harnesses.


2 separate light blue wires on two different wire covers. Pink ones comes off a T-block. Probed the wire from the pin harness connecter on inner firewall, next to pedals. Continuity shows they are connected when probing one to the other. I guessed what they were so don't mind the tags.



Tried to probe all on ECU/ECM on pass footwell. None are part of that.

 

The green wire with the white plug is the coolant temp gauge connector.

 

Is that the one on the sender on the drivers sides head?
If so, I think I have a wire for that already which we probed from the dash. It is the coiled pink wire wrapped in blue tape on the bottom of the second pic. Pretty sure the pink wire is an extension of another green wire.

 

yup , its for the temp gauge , its got the "hook" style connector . TPIparts.net sells the pigtail for 17 bones i think.

 

Every thirdgen I've ever worked on has had a connector like that, on a green wire to the coolant temp gauge sender. Pink or pink with a black trace is usually 12V+ switched. Wire colors can be reused throughout the car, so going just off color isn't going to tell you the whole story. Your best bet would be to get yourself a GM Service Manual or Electrical Diagnosis Service Manual Supplement for the year/make/model car you're working with and start studying. You can only get so far with a test light, DVOM, etc. Most of the time you have to go by the pigtail connector, location in the car/harness, and a wiring diagram.

 

The thing is, we have all that, like 4 different diagrams.
The two light blues I got marked as "choke heater" and "mixture solenoid" from what I can read on the diagram. Only don't know how to check for sure as both seem to connect to eachother.

 

Who's diagrams are you using? Some are better then others. Stick with GM diagrams and they're more likely to be accurate and complete. The later GM diagrams are easier to follow then early GM diagrams. Try to find a Service Manual a couple years newer with the later GM diagrams. As long as it's the same basic setup (carb to carb) they should be pretty close.

 

I have a Chilton's and a Haynes manual. The Haynes manual has A LOT more detailed wiring diagrams. The thing is, I don't know how to read the numbers and where they go to. The ECU is a lot easier to read, but they don't go there, they go to the driver's footwell. I want the service manual, but it'll take a week to get here from ebay.

 

Try your public library... The pickings are usually limited, but you might get lucky. Chiltons/Haynes usually don't have good diagrams. They tend to be really generic, and sometimes they mix and match details.

 

Public library here is no luck. I want to order the GM Service Manual off Ebay, but it's no point now as I'm almost done. That one green wire is not the one that goes to the temp gauge. I did a continuity test with that and another wire. The other wire (the pink one spoken about above) was continuous to the temp gauge. When I connected the unknown green wire to the pink/green wire, nothing happened. I am guessing it is not for the temp gauge or the wire is broken somewhere along the line, although that doesn't look like the case as it visually looks like it is in good shape. Still don't know the other two or that plug thing.