Pinpoint Test D: The Heated Exterior Mirror Is Inoperative
Rear View Mirrors - Exterior
Pinpoint Tests
Pinpoint Test D: The Heated Exterior Mirror is Inoperative
Refer to Wiring Diagram Set 56, Heated Window for schematic and connector information. Diagrams By Number
Refer to Wiring Diagram Set 124, Power Mirrors for schematic and connector information. Diagrams By Number
Normal operation
The rear window defrost/heated mirror switch is grounded through circuit 91S-HB31 (BK/OG). When the engine is running and the rear window defrost/heated mirror switch is pressed, the rear window defrost/heated mirror switch supplies a ground input to the Generic Electronic Module (GEM). The GEM then activates the rear window defrost/heated mirror relay by grounding the rear window defrost/heated mirror relay coil through circuit 15S-HB20 (GN/BK). When the rear window defrost/heated mirror relay is activated, voltage is supplied to the LH heated exterior mirror through circuit 15S-HB2 (GN/BU)/15S-HB15 (GN/BK)/15S-HB35 (GN/BK) and the RH heated exterior mirrors through circuit 15S-HB2 (GN/BU)/15S-HB28 (GN/OG)/15S-HB36 (GN/OG). Ground is supplied to the LH heated exterior mirror through circuit 31-HB35 (BK)/31-DA11 (BK)/31-DA8 (BK) and to the RH heated exterior mirror through circuit 31-HB36 (BK)/31-DA12 (BK).
- DTC B1343 (Heated Backlite Input Circuit Failure) - Sets when a short to ground is detected in the rear window defrost switch input circuit.
- DTC B1349 (Heated Backlite Relay Short to Battery) - Sets when a short to voltage is detected in the rear window defrost relay coil control circuit.
- DTC B1350 (Heated Backlite Relay Short to Ground) - Sets when an open or short to ground is detected in the rear window defrost relay coil control circuit.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Rear window defrost/heated mirror relay
- Rear window defrost/heated mirror switch
- Exterior mirror glass
- Exterior mirror
- GEM
PINPOINT TEST D: THE HEATED EXTERIOR MIRROR IS INOPERATIVE
NOTICE: Use the correct probe adapter(s) from the Flex Probe Kit when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
-------------------------------------------------
D1 RETRIEVE THE DTCs FROM THE GEM
- Ignition ON.
- Use the recorded GEM DTCs from the continuous and GEM self-tests.
- Are any DTCs retrieved?
Yes
For DTC B1343, GO to D12.
For DTC B1349, GO to D2.
For DTC B1350, GO to D13.
No
GO to D2.
-------------------------------------------------
D2 CHECK THE OPERATION OF THE HEATED EXTERIOR MIRROR GLASS
- Start the engine.
- Depress the rear window defrost/heated mirror switch to the ON position.
- Using an infrared temperature gun measure the temperature of the exterior mirror glass for approximately 30 seconds noting changes in temperature.
- Does the temperature of the exterior mirror glass rise?
Yes
The system is operating correctly at this time.
No
GO to D3.
-------------------------------------------------
D3 CHECK THE VOLTAGE TO THE INOPERATIVE EXTERIOR MIRROR
- Ignition OFF.
- Disconnect: LH Exterior Mirror C520 or RH Exterior Mirror C601.
- With the engine running, depress the rear window defrost switch to the ON position.
- Measure the voltage between ground and inoperative exterior mirror:
- LH: C520-4, circuits 15S-HB2 (GN/BU)/15S-HB15 (GN/BK)/15S-HB35 (GN/BK), harness side.
- RH: C601-4, circuits 15S-HB2 (GN/BU)/15S-HB28 (GN/OG)/15S-HB36 (GN/OG), harness side.
- Is the voltage greater than 10 volts?
Yes
GO to D4.
No
If a single LH or RH heated exterior mirror is inoperative, REPAIR the circuit. TEST the system for normal operation.
If both the LH and RH exterior mirror are inoperative, VERIFY Central Junction Box (CJB) fuse 167 (7.5A) is OK. If OK, GO to D5.
If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Diagrams By Number
-------------------------------------------------
D4 CHECK THE INOPERATIVE EXTERIOR MIRROR GROUND CIRCUIT FOR AN OPEN
- Ignition OFF.
- Measure the resistance between ground and inoperative exterior mirror:
- LH: C520-5, circuits 31-HB35 (BK)/31-DA11 (BK)/31-DA8 (BK), harness side.
- RH: C601-5, circuit 31-HB36 (BK)/31-DA12 (BK), harness side.
- Is the resistance less than 5 ohms?
Yes
CHECK the LH or RH exterior mirror jumper harness between the vehicle harness and the exterior mirror glass for open circuits and damaged or pushed-out pins. If the jumper harness is not OK, REPAIR the jumper harness. If the jumper harness cannot be repaired, INSTALL a new LH or RH exterior mirror. REFER to Exterior Mirror Exterior Mirror. If the jumper harness is OK, INSTALL a new LH or RH exterior mirror glass. REFER to Exterior Mirror Glass Exterior Mirror Glass. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D5 CHECK THE POWER TO THE REAR WINDOW DEFROST/HEATED MIRROR RELAY
- Ignition ON.
- Disconnect: Rear Window Defrost/Heated Mirror Relay.
- Measure the voltage between rear window defrost/heated mirror relay socket pin 85, circuit 15-DA1C (GN/YE) and ground; and between rear window defrost/heated mirror relay socket pin 30, circuit 30-DA1A (RD) and ground.
- Is the voltage greater than 10 volts?
Yes
GO to D6.
No
VERIFY Battery Junction Box (BJB) fuse 9 (40A) is OK. If OK, REPAIR the circuit. TEST the system for normal operation.
If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. REPAIR the circuit. TEST the system for normal operation. Diagrams By Number
-------------------------------------------------
D6 CHECK THE GEM OPERATION
NOTICE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.
- Start the engine.
- Activate the rear window defrost/heated mirror switch.
- Connect a 12-volt incandescent test light between rear window defrost/heated mirror relay socket pin 86, circuit 15S-HB20 (GN/BK) and rear window defrost/heated mirror relay socket pin 85, circuit 15-DA1C (GN/YE).
- Does the test light illuminate?
Yes
GO to D7.
No
GO to D8.
-------------------------------------------------
D7 CHECK THE REAR WINDOW DEFROST/HEATED MIRROR RELAY
- Ignition OFF.
- Carry out the rear window defrost/heated mirror relay component test.
- Did the rear window defrost relay pass the component test?
Yes
REPAIR open in circuit 15S-HB3 (GN/BU)/15S-HB40 (GN/OG) (LH door) or 15S-HB3 (GN/BU)/15S-HB41 (GN/BU) (RH door). TEST the system for normal operation.
No
INSTALL a new rear window defrost/heated mirror relay. CLEAR the DTCs. TEST the system for normal operation.
-------------------------------------------------
D8 CHECK CIRCUIT 15S-HB20 (GN/BK) FOR AN OPEN
- Ignition OFF.
- Disconnect: GEM C201B.
- Measure the resistance between rear window defrost/heated mirror relay socket pin 86, circuit 15S-HB20 (GN/BK) and GEM C201B-12, circuit 15S-HB20 (GN/BK), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to D9.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D9 CHECK THE REAR WINDOW DEFROST/HEATED MIRROR SWITCH INPUT
- While pressing and releasing the rear window defrost/heated mirror switch, measure the resistance between GEM C201B-11, circuit 31S-HB22 (BK/GN), harness side and ground.
- Is the resistance less than 5 ohms with the rear window defrost/heated mirror switch depressed; and greater than 10,000 ohms when the rear window defrost/heated mirror switch is released?
Yes
GO to D16.
No
GO to D10.
-------------------------------------------------
D10 CHECK CIRCUIT 31S-HB22 (BK/GN) FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Defrost Switch C241.
- Measure the resistance between rear window defrost/heated mirror switch C241-6, circuit 31S-HB22 (BK/GN), harness side and GEM C201B-11, circuit 31S-HB22 (BK/GN), harness side; and between rear window defrost/heated mirror switch C241-6, circuit 31S-HB22 (BK/GN), harness side and ground.
- Is the resistance less than 5 ohms between the defrost switch and CJB; and greater than 10,000 ohms between defrost switch and ground?
Yes
GO to D11.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D11 CHECK THE REAR WINDOW DEFROST/HEATED MIRROR SWITCH GROUND CIRCUIT
- Measure the resistance between rear window defrost/heated mirror switch C241-4, circuit 91S-HB31 (BK/OG), harness side and ground.
- Is the resistance less than 5 ohms?
Yes
INSTALL a new rear window defrost/heated mirror switch. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D12 CHECK CIRCUIT 31S-HB22 (BK/GN) FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: GEM C201B.
- Disconnect: Rear Window Defrost/Heated Mirror Switch C241.
- Measure the resistance between rear window defrost/heated mirror switch C241-6, circuit 31S-HB22 (BK/GN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new rear window defrost/heated mirror switch. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D13 CHECK FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Rear Window Defrost/Heated Mirror Relay.
- Start the engine.
- With the engine running, check the rear window defrost/heated mirror switch indicator status.
- Is the rear window defrost/heated mirror switch indicator illuminated?
Yes
REPAIR circuit 15S-HB3 (GN/BU) for a short to voltage. TEST the system for normal operation.
No
GO to D14.
-------------------------------------------------
D14 CHECK THE GEM OPERATION
NOTICE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table. To avoid connector terminal damage, use the Flex Probe Kit for the test light probe connection to the vehicle. Do not use the test light probe directly on any connector.
- Start the engine.
- Connect a 12-volt incandescent test light between rear window defrost/heated mirror relay socket pin 86, circuit 15S-HB20 (GN/BK) and rear window defrost/heated mirror relay socket pin 85, circuit 15-DA1C (GN/YE).
- Does the test light illuminate?
Yes
GO to D15.
No
INSTALL a new rear window defrost/heated mirror relay. TEST the system for normal operation.
-------------------------------------------------
D15 CHECK CIRCUIT 15S-HB20 (GN/BK) FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: GEM C201B.
- Measure the resistance between rear window defrost/heated mirror relay socket pin 86, circuit 15S-HB20 (GN/BK) and, harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to D16.
No
REPAIR the circuit. TEST the system for normal operation.
-------------------------------------------------
D16 CHECK FOR CORRECT GEM MODULE OPERATION
- Disconnect the GEM electrical connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect the GEM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new GEM. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
-------------------------------------------------