2002 Monte Carlo SS

[way2old]

Gotta fix this one. It is wife's car . Has 37,780 miles. Had the tires road force balanced and they had to break down one tire and re-index it. Since I have gotten the car back, the low tire pressure light stays on. I have tried to reset through light switch, didn't help. It says in owners manual it can be reset through radio. Mine does not have that option in the radio resets. If I can find out how the system works, it will be easier to look at. Someone said it is activated by the ABS, others say sensor in wheel. Any info appreciated as always. Happy Thanksgiving all.

[DanD]

Here's what I've got on this Tom.
Dan.
Tire Pressure Monitor Description and Operation
The Tire Pressure Monitor (TPM) system alerts the driver when a large change in the pressure of one tire exists while the vehicle is being driven. The TPM system uses the Electronic Brake Control Module (EBCM), ABS wheel speed sensor inputs, class 2 serial data circuit, and the Instrument Panel Cluster (IPC) message center to perform the system functions. The EBCM contains the software to calculate relative tire pressure differences. The software requires approximately 30 minutes of straight line driving in each of the three different speed ranges to complete the calibration process in order to have full capability of detecting a tire pressure condition. The speed ranges are as follows:
„h 24-64 km/h (15-40 mph)
„h 64-113 km/h (40-70 mph)
„h 113-145 km/h (70-90 mph)
Each speed range has 2 modes of tire pressure detection:
„h Monitor Mode 1
„h Monitor Mode 2
The EBCM learns the tire pressure calibration for each speed range independently. In Monitor Mode 1, the EBCM has only partially learned the tire pressure calibration for the speed range and has limited detection capability for a tire pressure conditions. In Monitor Mode 2, the EBCM has fully learned the tire pressure calibration for the speed range and has full detection capability for a tire pressure condition. Once the TPM system is calibrated the EBCM monitors the ABS wheel speed sensor inputs, which will all be the same as the learned calibration if the tire pressures stay the same. If the pressure increases or decreases in a tire, so too will that tires circumference and radius, which causes that wheel speed sensor input to change. The EBCM recognizes this change in wheel speed as a tire pressure condition. If the pressure in one tire becomes at least 69 kPa (10 psi) higher or lower than the other three the EBCM commands the IPC message center to display the LOW TIRE PRESSURE warning message via a class 2 serial data circuit. This warning message is a re-configurable telltale and is ranked as lowest priority and may not be displayed if a higher priority message is requested at the same time. This message does not appear if more than one tire has high or low pressure, or if the system is not calibrated properly. The TPM system does not alert the driver to which tire is high or low. To turn off the LOW TIRE PRESSURE warning message, refer to Tire Pressure Monitor Reset Procedure .


Tire Pressure Monitor Reset Procedure
Important
There are 3 different ways to reset the Tire Pressure Monitor (TPM) system. After resetting, the TPM system requires up to 30 minutes of straight line driving in each of the 3 speed ranges to complete the calibration process, for further information, refer to Tire Pressure Monitor Description and Operation . If the TPM system does not reset, or DTC C1245 remains current, refer to Diagnostic System Check - Tire Pressure Monitoring .
Using the exterior lamp switch
1. Adjust all tire pressures to the recommended kPa/psi. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication, or to Tire Placard in General Information.
2. Turn ON the ignition, with the engine OFF.
3. Cycle the exterior lamp switch from OFF to parking lamps 3 times within 5 seconds.
4. Use the scan tool in order to clear the TPM DTC.
Using the RDS radio, if equipped
1. Adjust all tire pressures to the recommended kPa/psi. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication, or to Tire Placard in General Information.
2. Turn the ignition to ACC or ON, with the engine OFF.
3. Turn the radio OFF.
4. Press and hold the DISP button until SETTINGS is displayed.
5. Press the SEEK up or down arrows until TIRE MON is displayed.
6. Press the PREV or NEXT button to enter the submenu. RESET will be displayed.
7. Press the DISP button, A chime will sound and DONE will be displayed.
8. Scroll until EXIT is displayed.
9. Press the DISP button to exit the TPM reset mode. A chime will sound to verify exit.
10. Use the scan tool in order to clear the TPM DTC.
Using the scan tool
1. Adjust all tire pressures to the recommended kPa/psi. Refer to Tire Inflation Pressure Specifications in Maintenance and Lubrication, or to Tire Placard in General Information.
2. Install the scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With the scan tool select Special Functions.
5. Select TIM Reset.
6. Press the Reset soft key.
7. Use the scan tool in order to clear the TPM DTC.

[way2old]

Thanks Dan. Gonna be hard to do the driving as printed. I have tried to reset through the lights, but the light stays on solidly. The only scan tool I have access to for GM is the OTC Nemesis. It seems like it is a hard fault, but there is no other concerns. Tire pressures are all 32psi. Drove it 250 miles this weekend to farm and back and no change. Talked to a friend that is Sm at GM dealer in Ohio and he says there is a possibility the Body Control Module is at fault. Thanks again for information. Might try to steal TECH tool from dealer one day and see if there is code in module. See ya.

[re-tired]

All of this to replace a stupid tire gauge. Thats progress. Good luck. If you cant reset, make the light go away.

[way2old]

I did see a nice SSR ;D