Ziggy*

Picked up a 90 coupe the other week. The seat belt warning light is on and stays on when seat belts are on...Thinking PO unhooked wire under seat....Also inflatable restraint light is on, PO said he took it to dealer. Told him couldn't get light to go out...lol Workin on getting FSM, New 4 post lift ordered. Getting to be the dreaded season out there....Time for shop and heaters...Any ideas till I get shop manual? Thanks ziggy

WVZR-1

I would say that you've got an issue with one of the sensors for the SIR and that will light both the DIC and the seatbelt icon in the cluster. It could be either side for the sensor error and there are numerous threads regarding the fix. Search is your friend for this. There are so many threads it's difficult to point you to a particularly good one.

Ziggy*

Thank You , Got 86 dash working...Now the 90...never ending...Love these ol' C4"s even more...Keeps me young...An limber....Lmao

ghlkal

I agree.

You likely don't have to replace the airbag sensors, just clean the connections. Getting to the sensors requires some time, but once you unbolt them, you'll see that the mounting surfaces need to be cleaned up.

Churchkey

After cleaning both sensors I added an external star lock washer to one of each sensor retaining bolts with a ground wire to other frame bolts.

The shop manual will give the sequence to eliminate the trouble lights. Timing the ground/no ground within 1/2 second can be tricky. A clock with a ticking second hand worked well for me.

Good luck.

Joe C

w/ the above, and I've got the same issue on my 90 - seat belt and SIR warning light. 90% of the time, you need to clean the sensor grounds, and clear the codes. typical 90 problem.

Ziggy*

Got my FSM , new lift will be here next week..26 degrees here tonight. Took the 90 out to top off fuel and Stabil for winter storage. Good time to sit by fire an read...lol Not a big fan of winter. Thanks for your help, Ziggy

ghlkal

Ziggy, that's a nice looking ride

Ziggy*

Thanks ghlkal...Was taking ride in 86 along river an passed her sitting with 4 sale sign...just wanted to "look"...lol Just got bugs out of 86 a month before....Everybody needs 2 corvettes, right???? ziggy

pipe

The sensors are on the frame rails close to the firewall disconnect the battery and wait a few minutes before doing any work. Remove the sensors and take a Dremel tool and sand the frame where the sensor sits and also the bottom of the sensor. Apply a coat of dielectric grease to the cleaned area. You could also put star washers on the bolts to help make a better ground when re attaching. Get yourself the mid America kit to remove the codes which hooks to the Aldl connector and then you go through the sequence to remove the code. The timing is very important to removing it. It might take a few tries. The kit is 20 bucks good luck. Pipe

Ziggy*

Pipe, Thanks for reply. Looked in Mid America catalog for 'kit". Couldn't find or online either??? Are you talking about one of those little Aldl plug in code scanners for OBD1? Hope you are enjoying all the snow you got.....Got about 1" here, but melting. Thanks ziggy

Ziggy*

Think I found what you were talking about in Ecklers catalog. The "Key" for pulling codes. I use a wire for "ECM" related problems. Made up a micro switch with wires for the "SIR" system. Plug in to pins "A" to "K", Stop watch in hand should do the trick. ziggy

Churchkey

Suggest a jumper wire to battery ground. Grounding to a painted seat frame can be "iffy".

Ziggy*

Pin "A" on ALDL is ground. Wire to "A" one to "K" is what I'm talking about...Heater fired up in shop...Going digging ziggy

Ziggy*

Pulled both side panels, To check on grounds for "SIR" . Added star washers while I was in there, They were cleaned ...Thinking maybe the "TECH" couldn't clear the code...."LIL" woman with stopwatch,an your guys help /plus FSM....no lights....One more happy 90 Corvette, plus owner....Took two times an one nasty look to pay attention to get her done...Thank you again

pipe

Hey zingy it says in the mid America catalogue infl rest reset tool. It plugs into the Aldl connector under the dash. It has a momentary contact button that ya just time it with a watch. Your welcome to use mine if ya like. Pipe

Ziggy*

Pipe, Thanks for your offer...Found what you were talking about on internet catalog. Made my own using micro switch....Took two times to get light off, all is well. Merry Christmas Ziggy