My new '99!!

[s2gots]

I finally got me a truck again...99 2500 GMC with the 3rd door...6.0 engine...runs absolutelly awesome...It has an 8" Cognito lift, Weld wheels, 35" BFG muds, 4:56 gears..superchip, and exhaust. Ive only had it two days, but so far, Im in love!!!LOL I do have a few minor issues that I knew about when I purchased, and was hopping I could get some help...first off, A/C problems, the fan speed selector works, the air flow adjustments work, such as defronst, or foot area, the A/C light comes on when its pressed, but no cold air comes out. All it blows is high temp heat, the temp selector does not seem to work when adjusting between cooler air, and warmer air. Just hot air. The compressor doesnt seem to cycle either.

Second is the ABS...the light is on and the brake light. The previous owner said he disconnected it a long time ago because he did not like how the ABS worked. Well this morning I found and pluged in the harness underneith the cab, and when plugged in , the ABS motor constantly runs.

Those are the only two things that are wrong with the truck...can someone shed some light on these things for me??

 

TIA

s2gots

[Rolandd]

Sounds like fun! See if you can find someone with a scan tool to pull the codes for the ABS issue. This will give you clues as to where to look next.

 

It sounds like you have two issues with the A/C system. One is that the temperature is not changing, the second is that the A/C system itself needs to be charged. The temp control should show up on a scan tool, which means you can determine if the problem is the control switch or the motor that controls the door in the heater box. While unlikely, it is possible that there is a mechanical issue with the door itself--either it is binding or has fallen off, allowing hot air to pass through all the time.

 

Good luck....

[asilverblazer]

The constantly running ABS motor is very common, and can be fixed by some companies, or replaced for a whole lotta cash. It could also have other issues with not being programmed for the proper tire size too.

[redvett]

Go here to fix the module.

http://www.modulemaster.com/

Lots of guy have had theres fixed by them.

[s2gots]

Sounds like fun!  See if you can find someone with a scan tool to pull the codes for the ABS issue.  This will give you clues as to where to look next.

 

It sounds like you have two issues with the A/C system.  One is that the temperature is not changing, the second is that the A/C system itself needs to be charged.  The temp control should show up on a scan tool, which means you can determine if the problem is the control switch or the motor that controls the door in the heater box.  While unlikely, it is possible that there is a mechanical issue with the door itself--either it is binding or has fallen off, allowing hot air to pass through all the time.

 

Good luck....

 

<{POST_SNAPBACK}>

 

 

 

Dealer today told me it could be the actuator???? If so, would this be easy to remove and replace? Also, the dealer said that a flash programming might fix the issue?? any thoughts

[Rolandd]

Sounds like fun!  See if you can find someone with a scan tool to pull the codes for the ABS issue.  This will give you clues as to where to look next.

 

It sounds like you have two issues with the A/C system.  One is that the temperature is not changing, the second is that the A/C system itself needs to be charged.  The temp control should show up on a scan tool, which means you can determine if the problem is the control switch or the motor that controls the door in the heater box.  While unlikely, it is possible that there is a mechanical issue with the door itself--either it is binding or has fallen off, allowing hot air to pass through all the time.

 

Good luck....

 

<{POST_SNAPBACK}>

 

 

 

Dealer today told me it could be the actuator???? If so, would this be easy to remove and replace? Also, the dealer said that a flash programming might fix the issue?? any thoughts

 

<{POST_SNAPBACK}>

 

 

 

 

Reflashing the computer simply means the dealer reprograms it for the correct tire sizes, gearing, etc. I do not understand how the ABS module knows that the tires are the wrong size, however enough folks have talked about it on this site and elsewhere that I believe that my lack of understanding does not make it false. The good news about a reflash is that your speedometer and odometer should correctly display speed and milage.

 

I will not claim to be an expert on ABS--my understanding is that the actuator is the expensive part that cuts the brake pressure 30-60 times a second to create the pulsing at the wheel. I do not know if this part is a monolithic piece that is unplugged and uncrewed from the brake lines and replaced or if internal components can be replaced. One would like to think that each channel's actuator solonoid can be replaced individually, however the factory may not want you tampering with pieces of the system in this way.

[redvett]

Myself i have never heard of a gear & tire size difference setting an ABS code but it will affect the PCM, ABS & SDM operations. Speedo being inaccurate is one of many.