more info on frame sensors

[rufcar]

I did both my sensors last yr on my 90 zr1. By spring both lights came back on. I reset them, that lasted 2 days. Somewhere I read adding a 2nd ground might help. I pulled the driver's side panel, battery and support and removed the sensor and cleaned it all again just because. Then I added a ground wire, ran it low under the firewall extension to a hinge screw I had removed and cleaned to bare metal. I cleared the codes and its been 2 weeks and it has not come back. I was also getting my ride control light but it never showed any codes. The main unit was repaired and so were the front shocks and motors. Even when lit all 3 settings worked perfectly. Since I added that ground, that light has never come back on either. Over the winter I might add one to the other side as well. I worked on and restored many Rolls-Royce and Bentely cars and grounds were always the problem. An early cloud series had 4 or more just on a single exhaust pipe for example.

[WARP TEN]

Like the Rolls and Bentleys, 30+ year old ZR-1 also have had plenty of problems with corroded grounds, and like you, many owners have found solutions to problems by cleaning and reattaching ground connections. Good work on yours. --Bob

[tf95ZR1]

OK, I'll ask.
What is a "frame sensor?"

[rufcar]

they are on all the c4 zr1s. There are 2 one below the battery on the frame and one just on the opposite side. GM installed them in case of a front-end collision, it stops your fuel pumps from pumping and other electrical items just not sure how many. In the 90 zr1 the ground wire has a grounding problem; all newer year's GM solved the problem. It sets off the passenger seat blet light and ALDL light on your DIC screen. Its been talked about on this and many forums since inception. The fix is to remove the sensors, grind both surfaces to bare metal and reattach, then clear the codes. Mine came back so I added an additional ground to the metal firewall/door jamb area.

[tf95ZR1]

I didn't know that.
Thanks!

I did some research and found this:

https://www.zr1.net/forum/showthread.php?t=19070&highlight=crash+sensor

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