I cant reset the clock on the radio of my 1998 GMC Sierra diesel truck. its factory so how do I reset it?

SOURCE: exhaust filter

Particulate filters are self cleaning. If the warning light comes on, you will need to take a long drive every so often to get the filter hot (It is a built-in part of the exhaust system.) Some models will also dump extra fuel int the system to help ignite the soot buildup and assist to "clean' the filter.
You need do nothing else; just get it really hot for a while each time the warning comes up. If you ignore it and do only short trips, it will clog up and need replacement.

SOURCE: 94 GMC truck diesel starts,runs and then dies and will not start

I have the same problem and have trouble codes 35 and 36. I found out that there is a computer module that needs replaced as it sits low in a valley and gets hot and seperates. I am reseaching about the a/m fix that installs the new module away from heat.

SOURCE: 1998 GMC Sierra radio and display stays on all the time

First of all...does your truck have the retained accessory power (RAP)? If it does, the radio would always stay on with the key off until you open the drivers door. If it does have RAP and the door pin on the drivers door has went bad, then the truck doesn't know that you opened the door and continues to allow accessory power (although it would still cut off after about 20 minutes). If the interior lights come on when you open the door, then the pin is ok. If the lights come on, it could be the RAP relay. If it has gone bad, it is possible it is stuck supplying power and needs replacing. The relay should be labeled in the fuse panel, and there should be other relays in the panel with the same part number. You can swap a relay for the RAP relay and see if it fixes the problem...if it does fix it swap the relays back and replace the RAP relay. If the truck doesn't have RAP then it is possible the problem is in the radio..if you have a friend with a GM car or truck close to the same year you could swap radios and see if that fixes your problem...should be pretty simple. pull the cover off the dash, it just clips on, take out a couple screws that hold in the radio, unplug it and plug in the other radio. sorry so long winded...hope this helps you somewhat.

Marvin

• 85242 Answers
• Posted on May 14, 2009

SOURCE: factory radio wiring color codes

Here ya go. enjoy!
2002 GMC Sierra C1500 Car Radio Wire Color Codes
Car Radio Battery Constant 12v+ Wire: Orange
Car Radio Accessory Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black/White
Car Radio Illumination Wire: Brown
Car Stereo Dimmer Wire: Gray
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: Under the center console.
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue

Dennis Mulford

• 1055 Answers
• Posted on Jun 06, 2009

SOURCE: 1998 GMC Sierra- runs rough then stalls when

had this problem on my neighbors 98 chevy truck with the same engine !!
it turnd out too be the fuel pressure regulator,you have too pull the upper intake too replace it!!