I've looked for the VSS buffer under the dash, behind the gauge cluster, next to the console area on driver side. I have looked same area on passenger side. I have looked through the hole that the radio would be in and this is all I find. Is this (see picture-the yellow thing) it? The pictures I've seen of buffers don't look like this yellow thing.This is a 1990 RS Camaro. Any clues? Thank you.

 

The yellow thing looks like a connector , joining two wires ?

I could be mistaken , and If I am I hope someone will correct this info , but , I thought that by 1990 the VSS buffer was built into the ECM and was no longer a separate little plastic box ?

 

Don't quote me, but I'm guessing it might be wiring for the airbag.

What does the yellow tag say?

 

It could be built in. I have no clue. I am very new to auto mechanic electrical. All I know is what I have read recently on-line. I am soooooo glad for the imput, cause my favorite saying is "more information is good". I can always see if others answer too, check even more on-line, and keep trying to trace things. My main problem is there is no power on C1 & C2 of gauge cluster pin #'s (C2)1-speed input, 3-oil pressure gauge, 4-fuel gauge; (C1) 1-infl rest indicator (maybe cause I have SIR fuse & such unplugged on this one), 2-SES indicator (maybe cause I have SIR unplugged), 4-temp gauge, 10-shift indicator, 11-security indicator (don't care at this point cause if it works I don't have codes if needed) (I'm the camaro babysitter, help repair-my working sons car). , 12-brake indicator. All other pins have power & the units they are for either work or now work. I have been reading to check up on sending units/sensors, how to use multimeter to test wires etc. Also getting reading clues as to how to remove fuel tank (or worst case cut hole) in case it's the sending unit. Have removed back seat to trace wiring and repaired the horn cam, wiring & fuse box for tail lights, fuse bypass to inline for "illumination" gauges. Switched the high/low selector to the floor since tried to reconnect the metal shaft in the steering column and move up the high/low selector. I am stumped on some of these. I have theoretically located the sensors for oil, water temp. , speed, and fuel. (on-line, on paper.) need to do the actual on the car finding & testing. I've also read up on how to repair and trace the circuit board back of cluster (this is electronic-no cables to back of cluster.) I've traced the circuits and written them on the printout of circuit in case need to deal with that. I've removed the gauge cluster. The steering wheel is still off (& airbag). Here I go ranting...

I watched a video on youtube on where the ECM is (under passenger side dash) & how to replace relays in it. I did not see any buffer for the speed sensor in the video (they didn't point it out at least). The relays were for left turn signal, right turn signal, courtesy lamps, flasher relay, DR ??, park tail lights, beam change. I will watch the video again- cause I watched it before I even heard of "buffers" so will be more alert now that you suggest it might be in there. Thank you-more information can't hurt.

 

I will get out the magnifying glass (hopefully in am-must fix supper!) and will see if I can read the tag. If it is wiring for airbag- there sure are a lot of various things for airbag-good thing that fuse is still out. Thank you.

 

 

You were correct-the yellow connector with tag had "inflate..." & was for the airbag.

I keep reading conflicting info (on-line) as to whether 1990 RS TBI has a buffer separate or not. I have looked for the buffer behind the instrument panel at the right. Thank you. The third picture I attached shows "behind the instrument panel to the right"-help! (See the light blue thing upper midleft- the brassy colored thing below that is the wiring harness pins for the gauges.) Then even further "right" (too much so I guess) is behind the center console (That was the picture with the yellow connector thing that turned out to be inflate...or airbag).

If 1990 RS TBI does not have a separate "buffer" as suggested previously, then am I right or wrong in figuring (the video I watched for 1990 Camaro on youtube showed this) location of ECM is under the dash passenger side? If the buffer is found in ECM, or I don't need a buffer at all, then I figure I should check this ECM to see what it has or does not have control over in this year vehicle. I did find a "schematic" "1990 5.0L Throttle body fuel injection engine wiring" in that 1982-1992 Camaro Guide Wiring book on-line. If this is the correct schematic for the ECM (all those pins or whatever they are) then the ECM video was not for this car-It had several relays in it but that was all I could see. This schematic lists all sorts of "C" this and "A, B, & D" that.

Thank you in advance- Anyone know where this ECM is? (In the mean time I will check under the passenger side dash just in case it's there.)

 

I did a bit of reading , and by 1992 the V6 had it's VSS built into the ECM , but it seemed to say that the V8 still had the separate VSS buffer like Nina showed in the picture . In my car , the VSS buffer is kinda buried in the dashboard on the passenger's side . The ECM on every third gen I've ever seen is also on the passenger's side and two bolts hold it's mounting bracket in , take them out and the ECM pulls down and out .

Here's a picture of when I replaced my dashboard . The ECM is the big silver box at the far right and it's kinda hard to see but the VSS is laying right next to the ECM to it's left . If I recall , the ECM doesn't require any thing taken apart except the lower plastic panel . I think the VSS buffer was deeper into the dashboard , though .....

 

Here is a diagram of the dash wiring for the speedo and some other indicators. This shows the buffer as part of the dash circuit board. HTH!

 

Thank you for more input. I went back out to the Camaro. I took some more pictures, looked deeper (and this time on the passenger side), to see if I could locate the buffer (as OrangeBird mentioned: It might be buried on the passenger side). I have not found it yet. I did find the ECM. It is only loosely bolted (and hangs down low which when I gently push up on it it has a lot of "play" as far as mounted goes-which seems like previous owner was tinkering with it).

I looked at the video again (Locating and fixing ECM relays): https://video.search.yahoo.com/video...t=mozilla&tt=b

I didn't see any thing that I could identify as a built in buffer (but that doesn't mean much as I am not sure what I am looking for. I will see if I can find wire colors that might give a clue on my "bunches" of diagrams & other parts-if able to trace them). Anyone see which part of the ECM I might check for a built in buffer?

I will try to get to the ECM removal over the next couple of days between "life's ordinary chores". I will then check more thoroughly behind for a yellow buffer-in case it is separate from ECM.

If the buffer is on the back of the gauge cluster (As bigal55 suggested to check-thank you for the diagram-it seems similar or same as one on Austins site-mine did show buffer in diagram but when looking at the actual cluster I'm like a dog chasing its tail-going in circles). I am not sure what to look for but here are pictures of the gauge cluster (front also to show type cluster). If anyone sees the part that might have the "buffer" please let me know. (Only thing is-if it is on the actual gauge cluster it will either be "another problem later" in addition to the problem now, or not a problem at all. (I say this because I am presently not getting any power to the pin on dash; haven't got as far as the gauge cluster itself until I get power to the pin first. Then I will either have working speedo or need to check further up the line toward gauge).

As I mentioned in my first posts: no power to pins for speedo, oil, fuel, & temp. (this is on dash, not on actual gauge cluster). (Can it be all these senders are bad?)(Can it be all these wires are bad or loose?) I keep looking at the diagrams & don't seem to see anything between the senders and the pin (except on the speedo & thus the buffer finding issue). I have checked the fuses. Gauge illumination now works. Gauge fuse has power to one side of fuse & only one wire not one on each side of the fuse, yet there IS power to C2 #14 "gauges power (gauges fuse)". The odometer works. The Tach works, the blinkers work (all on the gauge cluster). Like I said, I'm like a dog chasing its tail.

 

I think I might have the wire colors I need to try to trace. I may have to cut the binding on the wires to be able to hopefully trace them to find the "buffer" or try to see where they go (from the gauge pins).

 

90-92 V6 and TPI cars do not have a buffer box, 90-92 TBIs do. This was because the TBI ECM was a hold over adapted to the newer chassis

The buffer box is under the pass side dash near the ECM. Its either yellow like pictured above or cream colored