B276C-11
B276C-11-RIGHT HOOD HINGE PEDESTRIAN PROTECTION SQUIB - SHORT TO GROUND
Special Tools:
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
For description of the Electronic Pedestrian Protection Module (EPPM) Electronic Pedestrian Protection Hood Hinge Actuator - Description. For operation of the EPPM Electronic Pedestrian Protection Module - Operation. When powered, the EPPM sends a test current to the Electronic Pedestrian Protection actuator squibs to verify the integrity of the squib and the wiring. Use of the Supplemental Restraints System (8443A) in the tests below substitutes a suspect EPPM actuator squib with a known good component. The use of the SRS Load Tool (8443-25) provides a test point, as well as a method for opening the shorting bar connections within the harness connector. The EPPM is powered by a Ignition Run/Start (F943) control output circuit through the 32 pin connector side of the 56 way EPPM module connector. The 32 pin connector side of the 56 way EPPM module connector provides ground.
- When Monitored:
The EPPM sends out a 40mA diagnostic current on each squib voltage supply circuit at power up and every 200ms thereafter while the ignition is in on.
- Set Condition:
The EPPM will set this DTC if it detects short to ground on the EPPM Squib 2 circuits for more than 2.6 seconds. The DTC will go from active to stored when the module sees a recovery from the short to ground for more than 2.6 seconds.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. EPPM System Pre-Diagnostic Procedure.
Diagnostic Test
1. DETERMINE ACTIVE OR STORED DTC
NOTE: Make sure that the battery is fully charged.
NOTE: The scan tool, (8443A), and DVOM are required to perform the following test.
1. Turn the ignition on.
Select ACTIVE or STORED DTC:
ACTIVE DTC
- Go To 2
STORED DTC
- Go To 4
2. CHECK FOR SHORTED SQUIB CIRCUITS IN THE EPPM SQUIB 2 CIRCUITS
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.
1. Disconnect the EPPM squib harness connector.
NOTE: Check connectors - Clean and repair as necessary.
2. Connect the (8443A) and the (8443-10) to the Electronic Pedestrian Protection Hood Hinge Actuator harness connector.
3. If equipped with the keyless ignition, use this ignition on warning for EPPM.
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.
4. 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.
5. With the scan tool, read the active EPPM DTCs.
Does the scan tool display: B276C-11-RIGHT HOOD HINGE PEDESTRIAN PROTECTION SQUIB - SHORT TO GROUND - DTC?
Yes
- Go To 3
No
- Replace the Electronic Pedestrian Protection Hood Hinge Actuator. Electronic Pedestrian Protection Hood Hinge Actuator - Removal.
- Perform the EPPM SYSTEM VERIFICATION TEST. EPPM System Verification Test.
3. CHECK THE (R178) EPPM SQUIB 2 LINE 1 CIRCUIT AND THE (R179) EPPM SQUIB 2 LINE 2 CIRCUIT FOR A SHORT TO GROUND
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.
1. Disconnect the (8443A) and the (8443-10) from the Electronic Pedestrian Protection Hood Hinge Actuator Squib harness connectors.
2. Disconnect the EPPM harness connectors.
NOTE: Check connectors - Clean and repair as necessary.
3. Connect the SRS Load Tool (8443-25) to the EPPM module harness connectors.
4. Measure the resistance of the (R178) Electronic Pedestrian Protection Hood Hinge Actuator Squib 2 Line 1 circuit between the (8443-25) cavity 17 of the 24-way side and ground.
5. Measure the resistance of the (R179) Electronic Pedestrian Protection Hood Hinge Actuator Squib 2 Line 2 circuit between the (8443-25) cavity 18 of the 24-way side and ground.
Is the resistance below 10k Ohms on either circuit?
Yes
- Repair the EPPM Squib 2 circuits with resistance below 10k Ohms for a short to ground.
- Perform the EPPM SYSTEM VERIFICATION TEST. EPPM System Verification Test.
No
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.
- Replace the EPPM. Electronic Pedestrian Protection Module - Removal.
- Perform the EPPM SYSTEM VERIFICATION TEST. EPPM System Verification Test.
4. CHECKING STORED OR INTERMITTENT CODES
NOTE: Diagnose and repair all active codes before diagnosing stored codes.
1. With the scan tool, record and erase all EPPM System DTCs.
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.
2. Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors for chafed, pierced, pinched, and partially broken wires, and for broken, bent, pushed out, corroded, and contaminated terminals. Repair as necessary.
3. Reconnect all disconnected components and harness connectors.
4. If equipped with the keyless ignition, use this ignition on warning for EPPM.
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.
5. 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.
6. With the scan tool, monitor for active codes while performing the following:
- Wiggle the wiring harness and connectors of the related EPPM circuit.
- Continue the test until either a code becomes active or the problem area is isolated.
7. In the previous steps you have attempted to recreate the conditions responsible for setting the DTC in question / causing the intermittent condition.
Are any ACTIVE DTCs present?
Yes
- Diagnose and repair the DTC(s).
No
- No problem found at this time. Erase all codes before returning the vehicle to the customer.