Replacing Positive Cable

bmcduffy · September 21, 2005

Greetings

I just purchased a new positive battery cable from my local dealer. It has one wire more than the old wire I removed. (I don't think the old wire was OEM). The part number on the box is: 12157400.

I know the large one goes to the solenoid, the other longer one goes back up to the junction block on the firewall.

My question is, where do I connect the third wire? It is the same length as the main cable to the starter and is the same size and color as the wire that goes up to the junction block.

1990 C1500

5.0 litre

2 WD

Thanks in advance for any help you can offer.

redvett · September 22, 2005

If it was used on your model year it went to the alternator but i believe it was a later M/Y. Look in a 1990 Helms service manual to be sure.

bmcduffy · September 22, 2005

Well.......I did check in my Chilton's wiring diagram and it doesn't show the third wire. I don't think it could go to the alternator because there is no way it would reach.

This third wire teminates at the same spot as the large one does down by the starter. Is it some kind of back up? Should I just attatch it to the starter on the large lug with the large wire? Or......should I just cut it off and stop being a PITA?

Thanks

redvett · September 22, 2005

Well.......I did check in my Chilton's wiring diagram and it doesn't show the third wire. I don't think it could go to the alternator because there is no way it would reach.

This third wire teminates at the same spot as the large one does down by the starter. Is it some kind of back up? Should I just attatch it to the starter on the large lug with the large wire? Or......should I just cut it off and stop being a PITA?

Thanks

<{POST_SNAPBACK}>

A Chilton manual is a pice of crap it just gives you a general idea. Gm used the long one on certain years for low voltage. I believe it was 92-93 M/Y. It should hook to the alternador but if not cut it off. It only served a purpose for the assembly plant when the vehicle went through dynamic vehicle testing.

bmcduffy · September 22, 2005

Thanks Redvett

I also have a Haynes manual. It is for model years 1988-1990. It too only shows the two wire cable. I think my truck was right on the border for some changes between 1990-1991.

I am the one that changed out the original cable and it had only two wires so I will just cut off the third one.

I'm the original owner of this truck and I have always been a chevy guy. 15 years as a construction truck and I've done almost no repairs. I have always done the maintenance on time and it sure has paid off, what a great truck it has been!

Thanks again,

Boyd

bobcat5544 · September 22, 2005

THE THIRD ONE SHOULD BE FOR AN AUXILIARY BATTERY, BUT YOUR VEH WAS NOT EQUIPPED WITH SO YOU CAN CUST IT OFF OR USE IT TO POWER SOMETHING ELSE

redvett · September 22, 2005

Thanks Redvett

I also have a Haynes manual. It is for model years 1988-1990. It too only shows the two wire cable. I think my truck was right on the border for some changes between 1990-1991.

I am the one that changed out the original cable and it had only two wires so I will just cut off the third one.

I'm the original owner of this truck and I have always been a chevy guy. 15 years as a construction truck and I've done almost no repairs. I have always done the maintenance on time and it sure has paid off, what a great truck it has been!

Thanks again,

Boyd

<{POST_SNAPBACK}>

bmcduffy,

Thanks for buying your GM truck. As i stated in an earlier post the extra cable was used to satisfy production needs. This cable serves all needs for most applications.

BTW the Haynes manual is not the same as the Helms which is the OEM manual written by GM and used by dealers techs.

You understand the true value of maintenance but unfortunately most people do not. GM built K5 Blazers and 1Ton trucks built in the Flint plant in 1984-87 and they are still in heavy use today and as you know the military has high requirements on P/M.