1970 pigtails

[D S.]

I've owned my 1970 Corvette for four years and there are two electrical pigtails I cannot figure out what they are there for. In the two photos I've attached can you possibly tell me what these two pigtails are supposed to be connected to? They are in the engine compartment near the firewall. The one in the forefront has an orange wire and a light brown or brown wire. The one in the background has a black wire and a light brown or brown wire.

Thanks,
Scott Sims
Texas Chapter

[Martin N.]

Re: 1970 pigtails

SCOTT-

Do you have a GM Chassis Service Manual for your year? If so, look in the electrical section at the schematics and you should be able to trace them to find out what their use was / is. I suspect they'll be related to various combinations avaiable to your particular car based on destination and customer selections.

Marty

[D S.]

Re: 1970 pigtails

Thanks, Martin. I know in some later years GM installed pigtails made for this and that option wheter they were installed or not but the pigtails were left just dangling there. I have a feeling that one plug might be the original temperature sending unit lead that might have been by-passed by a previous owner as the original engine is MIA. The other pigtail? I tried tracing both using my assembly manual but that is like a maze. It doesn't show the wires in tandem to a specific plug configuration.

[Martin N.]

Re: 1970 pigtails

SCOTT-

Usually GM used a single dark green wire for their water temp. sending units up untill the 90's I beleive, so I think that'd rule out that possiblity since both of yours are 2 wires each. Orange & Tan and then Black & Tan, I'll scan thru mine 74 manual and see if there's any relation between the 2 years. I was a Buick Tech. and then a Service Manager back in the 70's & 80's so I'm used to reading all those colored lines that go on for pages and pages sometimes

Marty

[D S.]

Re: 1970 pigtails

Thanks, again, Marty. I was at the Texas Chapter NCRS Regional meet in Waco this last Saturday and I looked all down in that area and saw no connections or wires that were colored like that on three or four 1970 Corvettes. But I sure didn't dig down in there. I have a look-and-don't-touch policy. I'll bet the owners have a kill-and-ask-questions-later policy.

[Warren F.]

Re: 1970 pigtails

Scott,

Order the '70 laminated color wiring schematic from Dr. Rebuild. They are incredibly easy to follow and excellent.

[Dennis D.]

Re: 1970 pigtails

went out to check my 70 L-46 and don't appear to have those 2 connectors/ wire color combo. Don't see them in the service manual scematic either. (PITA to read) The Doc's color schematic is worth the price

[Jeremy D.]

Re: 1970 pigtails

Both 1970's AND the early '71 I have owned had the T.I. wires installed in the harness in case it was installed in a K66 car....they used a universal type harness, I guess. I can't remember what color they were or are, but I know my '70 base coupe has wires & plug for a TI distributor & box, just taped off. My '70 LT-1 had the regular points wires taped off, as does my '71 LT-1. Like I said, I can't remember the colors & such but maybe look into that direction...

[Stephen B.]

Re: 1970 pigtails

According to Dr. Rebuild's color harness poster the the black flat connector with orange and peach colored wires are for Accel Pedal TCS Switch for turbo 400 transmission.

[Dennis D.]

Re: 1970 pigtails

According to Dr. Rebuild's color harness poster the the black flat connector with orange and peach colored wires are for Accel Pedal TCS Switch for turbo 400 transmission.

explains why my 4 speed doesn't have it

[Stephen B.]

Re: 1970 pigtails

Yes, I'd agree.