TX_Mike

I have a quick question.

I notice today that when I press the button for my tow / od swtich, it does not come on. Anyone know what can be the problem?

Its the little button that is located at the end of the Automatic transmission shifer, Thanks

TX_Mike

Sorry, its a 2002 Silverado.

TX_Mike

ok. I know someone knows,right?

I called the chevy service dept here, they all play stupid saying they never had one w/ the light out or not working. The hell I will bring it to them to fix something that is a simple $50 part.

Trust me, I used to own a jeep, talk about nickle and diming yyour butt! I found the problems off the forums of jeep and saved thousands for easy parts to iinstall. So anyone know what this problem may be??

Thanks

RonH

What transmission do you have, and is the tow/haul modenot workingor is it just the light?

TX_Mike

Hi Ron.

Not sure what tranny it is, but yes, the light will not come on, as for the tranny, its not engaging when I push the button either. Any idea? Thanks

RonH

OK then, generically, it could be as simple as a defective switch. If it's not that, then it may be a problem in the electrical system. Or it might be a mechanical/hydraulic problem in the transmission. To really test it, you need a scan tool. Here's a simplified version of info from the service manual. Hopefully this will help you:

Tow/haul mode enables the operator to achieve enhanced shift performance when towing or hauling a load. When tow/haul mode is selected, the tow/haul switch input signal to the body control module (BCM) is momentarily toggled to zero volts. This signals the powertrain control module (PCM) to extend the length of time between upshifts and increase transmission line pressure. Cycling the tow/haul switch again disables tow/haul mode and returns the transmission to a normal shift pattern.

If the electrical circuit tests are OK and the tow/haul shift pattern is not occurring, there may be a mechanical/hydraulic condition that prevents tow/haul operation.

Tests

1 Test for a faulty tow/haul switch.
2 Test for voltage input from the BCM to the tow/haul switch.
3 Testfor voltage through the body wiring harness junction block.
4 Testfor ground integrity at the splice pack.

Hope this helps

ZX1100F1

RonH, has the correct sequence but you may find it very difficult or impossible to trouble-shoot this in your garage.

FYI: If you have a 2500 with the Duramax Diesel or 8.1 Liter Gas engine then you have an Allison LCT1000 Transmission If your truck came equipped with the 6.0 Liter Gas engine then you have a 4L80-E Transmission.
If your truck is a 1500 series then you have the 4L60-E