Operation CHARM: Car repair manuals for everyone.

C0077







C0077- LOW TIRE PRESSURE

For a complete wiring diagram REFER to DIAGRAMS/ELECTRICAL .

Theory of Operation


The tire pressure sensor actively monitors the air pressure and air temperature inside the tire, the sensors internal battery status, and the radial acceleration of the wheel. Each sensor has a unique ID code. The sensor transmits the data at regular intervals via an encoded signal to a receiver circuit located in the Wireless Ignition Node (WIN).


- When Monitored:
Continuously.

- Set Condition:
A low pressure condition will exist when the tire pressure falls below or is equal to the low pressure threshold value as specified for the vehicle.






Diagnostic Test


1. DTC STATUS IS ACTIVE
NOTE: If the incorrect Placard Values were programmed into the WIN, a DTC could be set. Before continuing with any Tire Pressure Monitor (TPM) diagnostic test, using the scan tool, check that the correct Placard Values have been programmed in to the module.

NOTE:
If the following conditions are present:

- Low Tire Pressure DTC (C0077) (Active)
- Spare Tire is not equipped with a Tire Pressure Sensor
- Spare Tire is currently on the vehicle
Repair the tire, place it back on the vehicle and test drive the vehicle. If the DTC(s) reset continue with the diagnostic procedure.


Turn the ignition on.
With the scan tool, select View DTCs in the Wireless Ignition Node (WIN).
Is the DTC status Active at this time?

Yes


- Go to 2


No


- Go to 4


2. LOW TIRE PRESSURE
Correct all tire pressure to the recommended specifications and wait 2 minutes.
With the scan tool, clear DTCs in the WIN.
Test Drive the vehicle for a minimum of 10 minutes with vehicle speed greater than 15 MPH (24 km/h).
With the scan tool, select View DTCs in the WIN.
Does the DTC reset or is the status Active for this DTC?

Yes


- Go to 3


No


- Test Complete.
- Perform TPM VERIFICATION TEST.Tire Pressure Monitor (TPM) Verification Test


3. TIRE PRESSURE SENSOR
NOTE: Before continuing, ensure the tire is free from any leaks or damage that would cause a low tire pressure condition. If a problem is found, repair as necessary and retest.

Turn the ignition off.
Replace the Tire Pressure Sensor indicating the low pressure condition.
With the scan tool, clear DTCs in the WIN.
Test Drive the vehicle for a minimum of 10 minutes with vehicle speed greater than 15 MPH (24 km/h).
With the scan tool, select View DTCs in the WIN.
Does the DTC reset or is the status Active for this DTC?

Yes


- Replace the WIN.
- Perform TPM VERIFICATION TEST.Tire Pressure Monitor (TPM) Verification Test


No


- Test Complete.
- Perform TPM VERIFICATION TEST.Tire Pressure Monitor (TPM) Verification Test


4. INTERMITTENT TIRE PRESSURE SENSOR DTC
The conditions necessary to set this DTC are not present at this time.
Refer to any Technical Service Bulletins that may apply to this condition.
With the scan tool, clear DTCs in the WIN.
Test Drive the vehicle for a minimum of 10 minutes with vehicle speed greater than 15 MPH (24 km/h).
With the scan tool, select View DTCs in the WIN.
Does the DTC reset or is the status Active for this DTC?

Yes


- Diagnose and repair the active DTC(s)
- Perform TPM VERIFICATION TEST.Tire Pressure Monitor (TPM) Verification Test


No


- Test complete.
- Perform TPM VERIFICATION TEST.Tire Pressure Monitor (TPM) Verification Test