Tire Pressure Monitoring

DTC C0550

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptor
DTC C0550
- ECU Malfunction

Circuit Description

The tire pressure module (TPM) receives a radio frequency (RF) transmission from each tire pressure sensor. Each sensor has its own unique identification (ID) code, which it transmits as part of each RF message, that must be learned into the TPM memory. Once all 4 IDs have been learned and vehicle speed is greater than 32 km/h (20 mph), the TPM continuously compares IDs in received transmission to its learned IDs to determine if all 4 sensors are present. If the TPM detects a low tire pressure condition or a malfunction in the system, it will appropriately illuminate tire pressure monitor indicator icon on the instrument panel cluster (IPC).

Conditions for Running the DTC

Vehicle speed is above 32 km/h (20 mph).

Conditions for Setting the DTC

* The IPC is not receiving a speed signal.
* Open/high resistance, short to ground, or short to voltage on the vehicle speed signal circuit between the IPC and the TPM.
* One of the tire pressure sensors is remaining in Drive mode after the vehicle is parked.
* An internal TPM malfunction.

Action Taken When the DTC Sets

TPM warning lamp on the IPC flashes for 75 seconds.

Conditions for Clearing the DTC

* The DTC will become history when condition for setting the DTC is no longer present.
* The TPM automatically clears the history DTC when a current DTC is not detected in 100 consecutive drive cycles.

Reference Information
Schematic Reference

Tire Pressure Monitoring System Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Tire Pressure Monitor Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
* Connector Repairs (Connector Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. With a scan tool, verify that the TPM is receiving the vehicle speed signal from the IPC while the vehicle is in motion.

• If a speed signal is not present, refer to TPM Speed Signal Malfunction below.

2. Perform the tire pressure sensor configuration procedure.
3. With a scan tool, perform the Tire Pressure Sensor Test in the Tire Pressure Monitor Special Functions menu and follow the on-screen instructions. The vehicle will need to be driven for at least 15 minutes above 31 mph during the test.

• If any sensor fails the test, replace the appropriate sensor.

4. Replace the tire pressure module and perform the tire pressure sensor configuration procedure.

Circuit/System Testing
TPM Speed Signal Malfunction

1. Ignition OFF, disconnect the IPC connector and TPM connectors.
2. Test for less that 5 ohm between the TPM connector terminal 2 and the appropriate connector terminal listed below.

* IPC X2, terminal 14 (notchback)
* IPC terminal 2 (hatchback)

• If greater that the specified value, test for an open/high resistance.

3. Test for infinite resistance between the appropriate connector terminal listed below and ground.

* IPC X2, terminal 14 (notchback)
* IPC terminal 2 (hatchback)

4. If less that the specified value, test for a short to ground.
5. Test for less than 3 V between the appropriate connector terminal listed below and ground.

* IPC X2, terminal 14 (notchback)
* IPC terminal 2 (hatchback)

• If greater than the specified range, test for a short to voltage.

6. If all circuits test normal, replace the TPM and perform the tire pressure sensor configuration procedure.

Repair Verification

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Tire Pressure Monitor System Configuration (Programming and Relearning)
* Tire Pressure Indicator Sensor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for TPM replacement, setup, and programming