'56 Series 62 A/C wiring question..!

[J. Gomez]

Happy days CLC members/readers..!

I’m on the final stages in finalizing the recondition of my front dash, and plugging all the wire connectors, light, etc. However, I have run into a particular problem that is driving nuts.

I overhauled the wiring hardness from the AC control panel to the compressor, one lead connects the AC clutch “hot” (Black), and the others are for the Idle speed-up control on the carburetor which is “positive and negative (Violet)”.  The hardness goes thought the firewall and terminates all wires at or around the AC control panel inside the car (per the length).

The service manual show the AC wiring under the Accessories Section 16, but it does not show the wiring arrangement for the Idle speed-up control. The Violet wire on mine was/is tapped (“Y” tap) inside the car (about 4” from the end) with a male connector on one end and a female connector on the other end.

I have accounted for “all” the wires and termination for each according to the schematic. I assumed the negative was tapped somehow within an existing “ground/negative” feed inside the car, I was wrong. I can’t find any were in the main hardness a “negative/ground” source for this type of arrangement.

Any help would be appreciated it.

Regards,

Jose Gomez CLC #23082

[J. Gomez]

Lou,

I have a Rochester carb!

My rationality in saying the “negative/ground” must be connected from inside the cab, is due to the removal of the original AC hardness, and the length of the wire with the “Y” tap from the firewall up to the AC control panel. All three wires were wrapped together from the engine compartment and at the “Y” tap (inside the cab) the Violet split from the bundle, while the rest extended up to the AC panel under the dash.

Thanks..!

Jose Gomez CLC #23082

[J. Gomez]

Lou,

I think I understand the setup (not 100% yet  need to test it), the connection you found going to the neutral switch “violet” enables the AC compressor to be energized “only” when the car is in “neutral” as specify in the manual under Section 10-2 which states “The Idle speed-up controls is designed to increase the engine idle RPM from 400 to 900 when the selector is in Neutral “N” position and the AC switch in “On”….”

BTW According to the wiring diagram the other side of the “Violet” wire (going up the main hardness) should go to the ignition switch “S” Solenoid position.

My previous assumption of the “Violet” been the negative/ground side for the idle speed-up control may be correct after all. If my theory is correct, the negative/ground side is being pick-up by the ignition switch through the “S” contacts and going to the starter solenoid “hold” coil which the opposite end is grounded.

I’ll check in the next day or so and provide feedback.

Again thanks a bunch for your assistance in checking yours…!!

Regards,

Jose Gomez CLC #23082

[J. Gomez]

Jose,

I crawled under my dash tonight, the violet wire does split as you said. One end (the round connector) plugs in at the Neutral switch.This is not found on the wiring diagram either.
The other violet wire(square connector) plugs into another violet wire that continues up to the instrument cluster from what i can see. Maybe it connects with the heater control switch

HTH,

Lou     

Lou,

Bingo it worked..! That was the missing key on my side by disconnecting the Violet lead from the neutral switch and splicing the "Y" tap wire from the AC hardness at the neutral switch the idle speed-up control solenoid worked like a champ.

Once again I do appreciate your help and efforts in checking yours.

Regards,

PS I’m attaching the AC wiring that also shows the wiring arrangement for the idle speed-up, it’s rough but serves the purpose.

Jose Gomez CLC #23082