B1A71
B1A71-01-PASSIVE ENTRY ANTENNA 1 - GENERAL ELECTRICAL FAILURE
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
For Antenna locations and the Theory of Operation, Passive Entry Module - Operation.
- When Monitored:
Whenever the Passive Entry or Keyless Go is activated.
- Set Condition:
When the driver starts the vehicle (through the push button switch) or activates the front door handles the PEM module fires the antennas and verifies the programed FOBIK. If it finds that the signal or return circuit of antenna 1 is open, short to ground, short to battery or the antenna terminals are shorted, it will set this code.
1. TEST FOR INTERMITTENT CONDITION
NOTE: If there is an antenna problem, the Keyless Go feature will not operate.
1. Using the FOBIK, turn the ignition on.
2. Using the scan tool, record and erase the DTCs.
3. With the scan tool, select: PEM, More Options and System Tests.
4. Perform the PEM LF Antenna Verification Tests.
5. With the scan tool, read the Active DTCs.
Does the scan tool display: B1A71-01-PASSIVE ENTRY ANTENNA 1- GENERAL ELECTRICAL FAILURE as active?
Yes
- Go To 2
No
- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
2. (D920) PASSIVE ENTRY ANTENNA 1 SIGNAL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Passive Entry Module C2 harness connector.
3. Measure the resistance between ground and the (D920) Passive Entry Antenna 1 Signal circuit.
Is the resistance below 30K Ohms?
Yes
- Repair the short to ground in the (D920) Passive Entry Antenna 1 Signal circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 3
3. (D920) PASSIVE ENTRY ANTENNA 1 SIGNAL CIRCUIT SHORTED TO VOLTAGE
1. Turn the ignition on.
2. Measure the voltage between ground and the (D920) Passive Entry Antenna 1 Signal circuit.
Is there any voltage present?
Yes
- Repair the short to voltage in the (D920) Passive Entry Antenna 1 Signal circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Go To 4
4. (D920) PASSIVE ENTRY ANTENNA 1 SIGNAL CIRCUIT OPEN
1. Turn the ignition off.
2. Disconnect the Passive Entry Antenna 1 harness connector.
NOTE: Antenna 1 is located in the Left Door.
3. Measure the resistance of the (D920) Passive Entry Antenna 1 Signal circuit between the PEM C2 harness connector and the Antenna 1 harness connector.
Is the resistance below 2.0 Ohms?
Yes
- Go To 5
No
- Repair the open in the (D920) Passive Entry Antenna 1 Signal circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
5. (D921) PASSIVE ENTRY ANTENNA 1 RETURN CIRCUIT OPEN
1. Measure the resistance of the (D921) Passive Entry Antenna 1 Return circuit between the PEM C2 harness connector and the Antenna 1 harness connector.
Is the resistance below 2.0 Ohms?
Yes
- Go To 6
No
- Repair the open in the (D921) Passive Entry Antenna 1 Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
6. (D920) PASSIVE ENTRY ANTENNA 1 SIGNAL CIRCUIT SHORTED TO THE (D921) PASSIVE ENTRY ANTENNA 1 RETURN CIRCUIT OPEN
1. Measure the resistance between the (D920) Passive Entry Antenna 1 Signal circuit and the (D921) Passive Entry Antenna 1 Return circuit.
Is the resistance below 30K Ohms?
Yes
- Repair the short between the (D920) Passive Entry Antenna 1 Signal circuit and the (D921) Passive Entry Antenna 1 Return circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.
No
- Replace the Antenna 1 and repeat the PEM LF Antenna Verification Tests. Passive Entry Antenna - Removal
- If this DTC is still active and there are no other DTCs present, replace the Passive Entry Module. Passive Entry Module - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.