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C1227



C1227-BRAKE PEDAL TRAVEL SENSOR CIRCUIT PERFORMANCE





When Monitored:

With the ignition on.

Set Condition:

When the Anti-Lock Brake Module indicates that the Brake Pressure Sensor Signal is not plausible.





Diagnostic Test

1. CHECK FOR A DTC C1227-BRAKE PEDAL TRAVEL SENSOR CIRCUIT PERFORMANCE

NOTE: This DTC must be active for the results of this test to be valid

Turn the ignition on.
With the scan tool read and record DTC's.
With the scan tool read and record Freeze Fame information.
With the scan tool erase DTC's.
Cycle the ignition from off to on.
With the scan tool, read and record DTC's.

Does the scan tool display: C1227-BRAKE PEDAL TRAVEL SENSOR CIRCUIT PERFORMANCE?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION diagnostic procedure. Testing and Inspection
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

2. CHECK THE TERMINALS/CONNECTORS/WIRING HARNESS FOR DAMAGE





Check the installation of the Brake Pedal Travel Sensor.
Check all related wiring for bruised chafed pierced or partially broken wires.
Check all related connectors for broken bent pushed out or corroded terminals.

Were any problems found?

Yes

- Repair as necessary
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test

No

- Go To 3

3. CHECK THE VOLTAGE ON THE (B237) BRAKE PEDAL TRAVEL SENSOR SUPPLY CIRCUIT





Turn the ignition off.
Disconnect the Brake Pedal Travel Sensor harness connector.
Turn the ignition on.
Measure the voltage of the (B237) Brake Pedal Travel Sensor Supply circuit.

Is the voltage above 4 volts?

Yes

- Go To 7

No

- Go To 4

4. CHECK THE (B237) BRAKE PEDAL TRAVEL SENSOR SUPPLY CIRCUIT FOR SHORT TO GROUND





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Using a 12-volt test light connected to 12-volts check the (B237) Brake Pedal Travel Sensor Supply circuit.

Does the test light illuminate brightly?

Yes

- Repair the (B237) Brake Pedal Travel Sensor Supply circuit for a short to ground.
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

No

- Go To 5

5. CHECK THE (B237) BRAKE PEDAL TRAVEL SENSOR SUPPLY CIRCUIT FOR SHORT TO VOLTAGE





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground check the (B237) Brake Pedal Travel Sensor Supply circuit.

Does the test light illuminate brightly?

Yes

- Repair the (B237) Brake Pedal Travel Sensor Supply circuit for a short to voltage.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

No

- Go To 6

6. CHECK THE (B237) BRAKE PEDAL TRAVEL SENSOR SUPPLY CIRCUIT FOR AN OPEN





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Connect a jumper wire between the (B237) Brake Pedal Travel Sensor Supply circuit and ground.
Using a 12-volt test light connected to 12-volts check the (B237) Brake Pedal Travel Sensor Supply circuit.

Does the test light illuminate brightly?

Yes

- Replace the Anti-Lock Brake Module.
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

No

- Repair the (B237) Brake Pedal Travel Sensor Supply circuit for an open.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

7. CHECK THE (B937) BRAKE PEDAL TRAVEL SENSOR RETURN CIRCUIT FOR SHORT TO GROUND





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Using a 12-volt test light connected to 12-volts check the (B937) Brake Pedal Travel Sensor Return circuit.

Does the test light illuminate brightly

Yes

- Repair the (B937) Brake Pedal Travel Sensor Return circuit for a short to ground.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

No

- Go To 8

8. CHECK THE (B937) BRAKE PEDAL TRAVEL SENSOR RETURN CIRCUIT FOR SHORT TO VOLTAGE





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground check the (B937) Brake Pedal Travel Sensor Return circuit.

Does the test light illuminate brightly?

Yes

- Repair the (B937) Brake Pedal Travel Sensor Return circuit for a short to voltage.
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

No

- Go To 9

9. CHECK THE (B937) BRAKE PEDAL TRAVEL SENSOR RETURN CIRCUIT FOR AN OPEN





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Connect a jumper wire between the (B937) Brake Pedal Travel Sensor Return circuit and ground.
Using a 12-volt test light connected to 12-volts check the (B937) Brake Pedal Travel Sensor Return circuit.

Does the test light illuminate brightly?

Yes

- Go To 10

No

- Repair the (B937) Brake Pedal Travel Sensor Return circuit for an open.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

10. CHECK THE (B137) BRAKE PEDAL TRAVEL SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Using a 12-volt test light connected to 12-volts check the (B137) Brake Pedal Travel Sensor Signal circuit.

Does the test light illuminate brightly?

Yes

- Repair the (B137) Brake Booster Travel Position Sensor Signal circuit for a short to ground.
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

No

- Go To 11

11. CHECK THE (B137) BRAKE PEDAL TRAVEL SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Turn the ignition on.
Using a 12-volt test light connected to ground check the (B137) Brake Pedal Travel Sensor Signal circuit.

Does the test light illuminate brightly?

Yes

- Repair the (B137) Brake Pedal Travel Sensor Signal circuit for a short to voltage.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

No

- Go To 12

12. CHECK THE (B137) BRAKE PEDAL TRAVEL SENSOR SIGNAL CIRCUIT FOR AN OPEN





Turn the ignition off.
Disconnect the Anti-Lock Brake Module harness connector.
Disconnect the Brake Pedal Travel Sensor harness connector.
Connect a jumper wire between the (B137) Brake Pedal Travel Sensor Signal circuit and ground.
Using a 12-volt test light connected to 12-volts check the (B137) Brake Pedal Travel Sensor Signal circuit.

Does the test light illuminate brightly?

Yes

- Go To 13

No

- Repair the (B137) Brake Pedal Travel Sensor Signal circuit for an open.
- Perform ABS VERIFICATION TEST VER 1. ABS Verification Test.

13. CHECK THE (B137) BRAKE PEDAL TRAVEL SENSOR SIGNAL CIRCUIT VOLTAGE OUTPUT





Turn the ignition off.
Reconnect the Anti-Lock Brake Module harness connector.
Reconnect the Brake Pedal Travel Sensor harness connector.
Turn the ignition on.
While back probing measure the voltage of the (B137) Brake Pedal Travel Sensor Signal circuit at the Brake Pedal Travel Sensor harness connector while depressing and releasing the brake pedal.

Is the voltage between O.15 volts to 4.85 volts?

Yes

- Replace the Anti-Lock Brake Module.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.

No

- Replace the Brake Pedal Travel Sensor.
- Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test.