jtrygstad

My 83S is a “barn-door” L-Jetronic with an auxiliary air valve. I discovered this past weekend that the lead running from the 14-pin connector (right front, red with white stripe) to auxiliary air valve heater-coil has no voltage. I discovered this problem because this same wire is used to trigger a relay to operate my aftermarket electric radiator fan since it turned on with the ignition key.

The engine harness (from 14 pin to various engine connections) is new, so fault appears to be within the older wiring encased in hardened sheathing that connects to a mysterious location.

Does anybody have any ideas where to I should start looking for the fault? Perhaps the CE panel? If I understand the wiring schematic correctly, it ultimately connects to the fuel pump relay. Any ideas are welcomed.

davek9

Here is the pin out for a 79, and the red/white is aux air, is it in the same pin location as your 83?

Here is the pinout for the 79':

#1 solid blue. goes to the Alternators B+ terminal
#2 blue/blk. Oil pressure sender unit
#3 blue/yellow. coolant temp sender
#4 blue white. oil pressure sender unit
#5 blue/green. coolant temp sender
#6 blue/brn. engine oil switch
#7 2 red/whites'. WUR and Sup air valve
#8 unused
#9 black. AC and AC pressure switch
#10 blk/yellow dot. Starter to resistor
#11 unused
#12 unused
#13 unused
#14 2 yellows. Large yellow-starter to fuse block; small yellow- to cold start valve

Edit: almost forgot, it connects to the "non-standard/expensive" Fuel Pump relay so that a signal from the Brain (on the inside right fender) tells the Fuel pump the engine is running and OK to send fuel. That would not be my first choice to run an electric fan signal from.

Ducman82

on the 83 pin 7 on the 14pin is the red/white for the sup air valve. it goes to pin Q1 on the CE panel and is grounded.

dr bob

Reminder that the "aux air valve" is used to compensate for the load of the air conditioning compressor when it's running. The valve bleeds extra air around the throttle. It is only active when the AC is on. Makes sense that it would also run the au cooling fan at the same time. So expect no voltage there unless the engine is running and AC is on.