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4L60E External Harness Ideas ?

3.9K views 9 replies 6 participants last post by  Z09B4U  
#1 ·
Hello,
I finally discovered I have a short in the: light blue with a white stripe. I plan on overlaying the wire and discounting the original wire. As finding the short in the harness seems very difficult. At the PCM is easy but the plug at the transmission is very tight. Any ideas to access the external plug at the transmission, with the transmission still installed. Need to spice wires down there.
Thanks Dezrat
 
#2 ·
That access is very difficult. Where are you located? If not in the rust belt you could remove the passenger side converter and heat shield and reach the transmission connector. Or you can remove the drive shaft and transmission crossmember and lower the transmission to access the connector. Do you know the location of the short?
 
#3 ·
Ken's got the idea. Although if you can squeeze and pull the the plug, then disconnect the pass O2, and the vss from the tails haft you may be able to pull everything back over to where it's mounted at the driverside bellhousing. Should then hang down low enough to work with the plug.

-Brian
 
#4 ·
Yeah, it has been a while, I remember it as awkward, not impossible.

If it is truly damaged, shorted to ground I would recomend finding out where and correcting the issue rather than bypassing.
Why?, because the likelyhood of only one wire being damaged is pretty low even though it is the only issue at this time.
A very common area for issue is around the right rear of the engine, especially if the trans has been out.

When you get the trans plug undone, before moving anything else, i would recomend seeing if that circuit is cross connected to any other by doing a continuity check between its PCM pin and all others as well as engine ground.
This as well as checking both ends of this circuit, at the trans and PCM , for proper continuity
 
#5 ·
Thanks fellows, all good suggestions and useful tips. I am the original owner and the car has 66K, San Diego miles on it. I have been chasing this gremlin for a least two years. I have verified it is a ground out problem. The reason I want to bypass the original wire is to verify that it stops the 073 code (force motor) then I will go back and look for a damaged wire or harness. The trans or motor has never been out of the car. This is a very nice car. After thinking last night, believe I can snip the wire up and away from the connector then pull the individual wire down and soldier the new wire to the existing wire near the plug. I have another plug if I want to change out pins later. Maybe when the transmission is out.
Thanks again and Cheers: Dezrat
 
#6 ·
Update and thank you to all. Disconnected O2 sensor and a plug near the O2 sensor, then was able to slide trans connector over top of the trans and drop down on the left side. Per Brian’s suggestion. Then saw where the shorted wire had popped out of the plastic harness in a pigtail shape and wore thru the sheathing. It was a direct short to to the top of the bell housing. Found problem and called it a day.
Now considering disconnecting VSS and trans bellhousing bolt with bracket holding harness. Then pulling the whole harness up into the engine compartment for a proper repair. Thanks to all for responding, gave me the push to find the problem and repair it properly. Dezrat
 
#8 ·
Thanks to all, my car is shifting great now. No codes, had a direct short to the bellhousing. Repaired just in time first for the summer So. Cal cruize seen. Been a great car. Dezrat
 
#10 ·
I just watched a 1950s film on crank bearings. A major part of the information was on how to get a customer to understand what caused a problem and that more than the immediate problem would have to be fixed.

I expect the first guy to sell a wheel soon had a customer who wanted a "cheap fix"

As anyone in the repair business learns not everyone likes what they want fixed. It is hard sometimes to fix something when you want to take more time to either "put it back to factory" or "make it better than new". This forum seems better than others because a lot of members "want to do it right" or better. Other forums seem to have more members that just flog a car to death or think that a 25 year old car should run perfectly without maintenance.

Desrat It is great you got the car fixed without a bad shop bleeding a pile of money from you. I have run old cars all my life and try to remember the good guys who gave me free information instead of charging me "diagnostic fees" or finding a problem that was not real.

The transmission harness wire breaking or shorting has happened on various makes and models. Lucky your car could tell you some of the problem. Sometimes the only way is to just unplug and test the harness.