Anyone have haywire gauges remedies?

[anotheridiot]

Working on this burnt trailblazer, going thru the bugs and have a tach, speedometer and oil pressure gauge a little off or not working. The speedo increases and stays there, dont know if it is a low signal, the tach barely moves, oil pressure after a change is about 15, surprisingly the Hayes book says 12 minimum at 1200 rpms. Volt, temp and fuel seem ok, Saw a rebuild service on ebay for about the cost of a used cluster, do not know where the mileage is stored though, dont want to buy a used cluster and have the odometer reading 300k instead of 144.

[silver_bullet]

The odo is stored internally in the cluster..... usually have to have a service repair facility reset it.... here's what I was able to find:

https://www.google.com/search?q=GM+instrument+cluster+service&oq=GM+instrument+cluster+service&aqs=chrome..69i57j0.10749j0j7&sourceid=chrome&ie=UTF-8

[SuperBuickGuy]

The odo is stored internally in the cluster..... usually have to have a service repair facility reset it.... here's what I was able to find:
https://www.google.com/search?q=GM+i...hrome&ie=UTF-8

a friend got the cluster out of my 2002 Denali and put it in his 2004 Suburban - the correct mileage for the Suburban displayed when he powered it up....

as for unreliable gauges - those tend to be a grounding issue.... but with all the things they depend upon, all I can say is good luck

[anotheridiot]

Did not touch anything on the harness going inside. There was one low range gray wire in the 12 wire tranny plug, but since it was the only gray it had to go to the right place. I looked up flashing a PCM and they say you have to enter the vin and then the mileage, so I agree I think the computer has that number for any gauge that goes in there. Just seems odd only 3 of them are not working, just happen to be three important ones.
Cant find the signal for the tach, I figured it would somehow be tied to the cam or crank sensor telling a coil to fire.

I did bring the PCM with the harness I got from the junk yard that I have spliced in, just in case this one was damaged, but I know it will just be on security if I try to plug it in now.

[silver_bullet]

Our newest is a 2002.... swapped cluster out, and it never updated...we recorded both, and what's funny is that the BCM has the correct mileage according to our Snap On scanner...

[oletrux4evr]

I'm with SBG.....grounding issue. Gray wires in my cars are lighting...........

[anotheridiot]

Well, for good or bad, a guy on ebay took my 52.00 offer for a 65.00 auction, so I guess I will see where the numbers come from.

Dropping the tank today since one of the lines was spraying fuel, went to rock auto to check pumps, look like they all have metal tops, so I dont think the quick connect is cracked like usually happens when you jossle lines around, but put the TYC part number in Amazon and it came up for 19.00, did not want to pass that up before they fixed it.

So when the new one gets here the car should be down and we will see. I guess worst case you take out the steeper motors that work?

[anotheridiot]

took longer than expected to get the right ends to replace the fuel lines. Put a 5/16 regular jiffy connector on the return and it fit fine, so I just figured the other was a regular 3/8, nope, something called a bundy connector. No matter how bad I try to stock up on this stuff, a new connector rears its ugly head. I am glad none of the 5/8ths one needed anything other than the lock clips.

anyway, only "good" thing that happened is the gauges plugged in and all worked, and the odometer was at 137K, original was at 144. I was really expecting a 2-300,000 number. I guess we see if anything changes or updates eventually, at least I know we have oil pressure now.