Popeye65

98 Tahoe
I entered the 'programming' mode in the OBDII (connect pin 4 and 8) as directed in [http://programyourremote.com/classified/DisplayAd.asp?id=376] to re-program the remote key fob as one had a battery issue. The process was successul.

This was done yeterday and today i noticed the RPM guage not working. At this moment i have no other issues, i.e bad idle or anything like that. Is the RPM guage working on a fuse (i could not find one). This is realy baffling me.

What could be the cause?

j cAT

you just purchased this vehicle ???
the vehicle history should be examined for odometer tampering...

Popeye65

Carfax verified before purchase, previous owner a old lady, truck was parked for a Year.

Hoping to go through all the fuses (even if they do not pertain to RPM or not) today .. hoping against hope of a loose connection somewhere or a blown fuse.

__________________
Some days you are the windshield .... most days you are the bug

Popeye65

Cause : Still unknown
Symptom: Remove the battery terminal and replace it after some time and the RPM gauge seems not to work (i have recreated this issue, time & time again to verify)
Solution: Remove and replace the #4 Fuse on the driver side fuse panel and it seems to resolve the issue.

If some one knows why this is happening i really like to know.

__________________
Some days you are the windshield .... most days you are the bug

j cAT

what is the size and name of the fuse....usually it will have a name ecm,courtesty lts, etc...also amperage..

who told you it was a old lady that previously owned this ...the car salesman..

that is a very common b/s line

Carsrcool100

Thats something i would do. Just try to go through the fuses and see if you find a problem. If not there is always proffesional help.

Popeye65

Fuse name is "gauges" and it is 10A

I bought it from the "ol lady" herself, took it from her home/yard and she signed for the ownership.

__________________
Some days you are the windshield .... most days you are the bug

j cAT

the removal of the battery terminal,, hopefully negative terminal not positive ,, when the key is not in the ignition switch , causes the gauges fuse to blow ,,,then only the tach is inoperative ...Is this your problem or not?

you should never remove the positive terminal unless the negative is removed first....also never screw with these battery connections when the engine is running or you WILL need a new pcm/computer...

since you also have problems with odometer/speedometer it is very possible that the vehicle suffered damage when jump started or some other surge damage..since it was sitting for a period of time,,,