Diagnostic Test
- DETERMINE ACTIVE OR STORED DTC NOTE:
Make sure the battery is fully charged.
- Turn the ignition on.
- With the scan tool, read EPPM DTCs.
Is the DTC active or stored?
EPPM - ACTIVE DTC
- Go To 2.
EPPM - STORED DTC
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM INTERMITTENT TEST.
- CHECK FOR ADDITIONAL ACTIVE SATELLITE SENSOR DTCS NOTE:
The scan tool, (special tool #8443-25, 56 Way ACM Adapter), and a DVOM are required to perform the following tests.
- CHECK (R174) CENTER PEDESTRIAN IMPACT SENSOR SIGNAL CIRCUIT FOR AN OPEN WARNING:
Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Disconnect the Center Pedestrian Impact Sensor harness connector.
- Disconnect the EPPM harness connectors.NOTE:
Check the connectors - Clean and repair as necessary.
- Connect the (special tool #8443-25, 56 Way ACM Adapter) to the EPPM harness connectors.
- Measure the resistance of the (R174) Center Pedestrian Impact Sensor Signal circuit between the Center Impact Sensor harness connector to the (special tool #8443-25, 56 Way ACM Adapter) connector cavity 32 - 29.
Is the resistance below 1.0 Ohm?
Yes
- Go To 4.
No
- Repair or replace the (R174) Center Pedestrian Impact Sensor Signal circuit for an open in accordance with the Service Information. Then, Go To 4.
- CHECK (R175) CENTER PEDESTRIAN IMPACT SENSOR GROUND CIRCUIT FOR AN OPEN
- Measure the resistance of the (R175) Center Pedestrian Impact Sensor ground circuit between the Center Front Impact Sensor harness connector and the (special tool #8443-25, 56 Way ACM Adapter) connector cavity 32 - 30.
Is the resistance below 1.0 Ohm?
Yes
- Go To 5.
No
- Repair or replace the (R175) Center Pedestrian Impact Sensor ground circuit for an open in accordance with the Service Information.
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.
- Measure the resistance of the (R175) Center Pedestrian Impact Sensor ground circuit between the Center Front Impact Sensor harness connector and the (special tool #8443-25, 56 Way ACM Adapter) connector cavity 32 - 30.
- CHECK (R175) CENTER PEDESTRIAN IMPACT SENSOR GROUND CIRCUIT FOR A SHORT TO THE (R174) CENTER PEDESTRIAN IMPACT SENSOR SIGNAL CIRCUIT
- Measure the resistance between the (R174) Center Pedestrian Impact Sensor Signal circuit cavity 2 and the (R175) Center Pedestrian Impact Sensor ground circuit cavity 1 at the Center Pedestrian Impact Sensor harness connector.
Is the resistance below 5K Ohms?
Yes
- Repair or replace the (R174) Center Pedestrian Impact Sensor Signal circuit for a short to the (R175) Center Pedestrian Impact Sensor ground circuit in accordance with the Service Information.
- Refer to MODULE, ELECTRONIC PEDESTRIAN PROTECTION, REMOVAL and perform the EPPM SYSTEM VERIFICATION TEST.
No
- Go To 6.
- Measure the resistance between the (R174) Center Pedestrian Impact Sensor Signal circuit cavity 2 and the (R175) Center Pedestrian Impact Sensor ground circuit cavity 1 at the Center Pedestrian Impact Sensor harness connector.
- CHECK (R174) CENTER PEDESTRIAN IMPACT SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance of the (R174) Center Pedestrian Impact Sensor Signal circuit between ground and the Center Pedestrian Impact Sensor harness connector cavity 2.
Is the resistance below 6K Ohms?
Yes
- Repair or replace the (R174) Center Pedestrian Impact Sensor Signal circuit for a short to ground in accordance with the Service Information.
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.
No
- Go To 7.
- Measure the resistance of the (R174) Center Pedestrian Impact Sensor Signal circuit between ground and the Center Pedestrian Impact Sensor harness connector cavity 2.
- CHECK (R174) CENTER PEDESTRIAN IMPACT SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
If equipped with the standard key ignition, use this ignition on warning.
WARNING:Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If equipped with the keyless ignition, use this ignition on warning.
WARNING:Disconnect the 12-volt battery wait two minutes before proceeding, remove the EPPM fuse, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the EPPM fuse. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Measure the voltage of the (R174) Center Pedestrian Impact Sensor Signal circuit between the Left Front Impact Sensor harness connector cavity 2 and ground.
Is there any voltage present?
Yes
- Repair or replace the (R174) Center Pedestrian Impact Sensor Signal circuit for a short to voltage in accordance with the Service Information.
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.
WARNING:Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
No
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST. If DTC U11A0-00-LOST COMMUNICATION W/CENTER PEDESTRIAN PROTECTION SATELLITE ACCELERATION SENSOR is still active, Go To 9. Otherwise, test complete.
- Measure the voltage of the (R174) Center Pedestrian Impact Sensor Signal circuit between the Left Front Impact Sensor harness connector cavity 2 and ground.
- CHECK (R172) RIGHT PEDESTRIAN IMPACT SIGNAL CIRCUIT AND (R174) CENTER PEDESTRIAN IMPACT SENSOR SIGNAL CIRCUIT AND (R170) LEFT PEDESTRIAN IMPACT SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE WARNING:
Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Disconnect the Center Pedestrian Impact Sensor Signal circuit harness connector.
- Disconnect the Right Pedestrian Impact Sensor Signal circuit harness connector.
- Disconnect the Left Pedestrian Impact Sensor Signal circuit harness connector.
- Disconnect the EPPM harness connectors.NOTE:
Check the connectors - Clean and repair as necessary.
- Connect the (special tool #8443-25, 56 Way ACM Adapter) to the EPPM harness connectors.
If equipped with the standard key ignition, use this ignition on warning.
WARNING:Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If equipped with the keyless ignition, use this ignition on warning.
WARNING:Disconnect the 12-volt battery wait two minutes before proceeding, remove the EPPM fuse, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the EPPM fuse. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Measure the voltage of the (R174) Center Pedestrian Impact Sensor Signal circuit between the (special tool #8443-25, 56 Way ACM Adapter) cavity 32 - 29 and ground.
- Measure the voltage of the (R170) Left Pedestrian Impact Sensor Signal circuit between the (special tool #8443-25, 56 Way ACM Adapter) cavity 24 - 12 and ground.
- Measure the voltage of the (R172) Right Pedestrian Impact Sensor Signal circuit between the (special tool #8443-25, 56 Way ACM Adapter) cavity 24 - 9 and ground.
Is there any voltage present?
Yes
- Repair or replace the impact sensor circuit with voltage present for a short to voltage in accordance with the Service Information.
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.
WARNING:Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
No
- Go To 9.
- CHECK OPERATION OF CENTER PEDESTRIAN IMPACT SENSOR WARNING:
Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Replace the Center Pedestrian Impact Sensor. Refer to SENSOR, IMPACT, REMOVAL .
- Reconnect the vehicle body harness to the impact sensor.
- Remove any special tools or jumper wires and reconnect all previously disconnected components - except the Battery.
If equipped with the standard key ignition, use this ignition on warning.
WARNING:Turn the ignition on, then reconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
If equipped with the keyless ignition, use this ignition on warning.
WARNING:Disconnect the 12-volt battery wait two minutes before proceeding, remove the EPPM fuse, connect the 12-volt battery, wait two minutes before proceeding. Cycle the ignition to the On position, then reconnect the EPPM fuse. Wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
- Connect the scan tool to the Data Link Connector - use the most current software available.
- With the scan tool, erase all codes in the EPPM.
- Perform EPPM module reset. Access the Diagnostic Procedures menu from the EPPM ECU Overview screen on the scan tool to perform this operation.
- Wait one minute, and read active codes.
Did the active DTC U11AO-00-LOST COMMUNICATION W/CENTER PEDESTRIAN PROTECTION SATELLITE ACCELERATION SENSOR return?
Yes
- Replace the EPPM in accordance with the Service Information. Refer to MODULE, ELECTRONIC PEDESTRIAN PROTECTION, REMOVAL .
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.
WARNING:If the Electronic Pedestrian Protection Module (EPPM) is dropped at any time, it must be replaced. Failure to take the proper precautions can result in accidental actuator deployment. Failure to follow these instructions may result in possible serious or fatal injury.
WARNING:Turn the ignition off disconnect the 12-volt battery and wait two minutes before proceeding. Failure to follow these instructions may result in possible serious or fatal injury.
No
- Repair is complete.
- Refer to STANDARD PROCEDURE and perform the EPPM SYSTEM VERIFICATION TEST.