Pinpoint Test G: The Heated Windshield is Inoperative or Does Not Operate Correctly
Glass, Frames and Mechanisms
Pinpoint Test G: The Heated Windshield is Inoperative or Does Not Operate Correctly
Refer to Wiring Diagrams Set 56, Heated Window for schematic and connector information. Electrical Diagrams
Normal Operation
When the engine is running and the heated windshield defrost switch is pressed, the defrost switch supplies a ground input to the Generic Electronic Module (GEM). The GEM (Generic Electronic Module) then activates the left and right heated windshield relays which supply voltage to the heated windshield defrost grids. The left and right heated windshield defrost grids do not share any common power or ground circuits. The heated windshield defrost switch Light Emitting Diode (LED) is illuminated whenever the right heated windshield relay is active.
- DTC B2113 (Heated Windshield Input Short to Ground)- Sets when the heated windshield defrost switch is active during an on-demand self-test or when a short to ground is detected in the heated windshield defrost switch input circuit.
- DTC B2248 (Heated Windshield Relay Coil Circuit Failure)- Sets when a short to voltage is detected in the left and right heated windshield relay coil control circuit.
- DTC B2256 (Front Window Heater Relay Short to Ground)- Sets when an open or short to ground is detected in the left and right heated windshield relay coil control circuit.
This pinpoint test is intended to diagnose the following:
- Fuse(s)
- Wiring, terminals or connectors
- Left heated windshield relay
- Right heated windshield relay
- Defrost switch
- Heated windshield defrost grid
- GEM (Generic Electronic Module)
PINPOINT TEST G : THE HEATED WINDSHIELD IS INOPERATIVE OR DOES NOT OPERATE CORRECTLY
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.
G1 RETRIEVE THE DTCs FROM THE GEM (Generic Electronic Module)
- Ignition ON.
- Use the recorded GEM (Generic Electronic Module) DTCs from the continuous and GEM (Generic Electronic Module) self-tests.
Is DTC B2113 present?
Yes
GO to G2.
No
If both heated windshield defrost grids are inoperative, GO to G4.
If a single heated windshield defrost grid is inoperative, GO to G10.
G2 CHECK THE HEATED WINDSHIELD DEFROST SWITCH CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: GEM (Generic Electronic Module) C201B.
- Measure the resistance between GEM (Generic Electronic Module) C201B-8, circuit 31S-HB9 (BK/WH), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to G15.
No
GO to G3.
G3 CHECK THE HEATED WINDSHIELD DEFROST SWITCH CIRCUIT FOR A SHORT TO GROUND WITH THE SWITCH DISCONNECTED
- Disconnect: Defrost Switch C241.
- Measure the resistance between GEM (Generic Electronic Module) C201B-8, circuit 31S-HB9 (BK/WH), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
INSTALL a new defrost switch. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
G4 CHECK THE HEATED WINDSHIELD DEFROST SWITCH CIRCUIT 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 at the beginning. 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.
- Ignition OFF.
- Disconnect: GEM (Generic Electronic Module) C201B.
- Connect a 12-volt incandescent test light between GEM (Generic Electronic Module) C201B-8, circuit 31S-HB9 (BK/WH) and the battery positive post.
- Activate the heated windshield defrost switch while observing the test light.
Does the test light illuminate when the heated windshield defrost switch is pressed?
Yes
GO to G7.
No
GO to G5.
G5 CHECK THE DEFROST SWITCH GROUND CIRCUIT
- Disconnect: Defrost Switch C241.
- Measure the resistance between defrost switch C241-4, circuit 91S-HB31 (BK/OG), harness side and ground.
Is the resistance less than 5 ohms?
Yes
GO to G6.
No
REPAIR the circuit. TEST the system for normal operation.
G6 CHECK THE HEATED WINDSHIELD DEFROST SWITCH CIRCUIT FOR AN OPEN
- Disconnect: Defrost Switch C241.
- Measure the resistance between defrost switch C241-1, circuit 31S-HB9 (BK/WH), harness side and GEM (Generic Electronic Module) C201B-8, circuit 31S-HB9 (BK/WH), harness side.
Is the resistance less than 5 ohms?
Yes
INSTALL a new defrost switch. TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
G7 CHECK THE POWER TO THE LEFT HEATED WINDSHIELD RELAY
- Disconnect: Left Heated Windshield Relay.
- Ignition ON.
- Measure the voltage between left heated windshield relay socket pin 1, circuit 15-HB7 (GN/BU), and ground.
Is the voltage greater than 10 volts?
Yes
GO to G8.
No
REPAIR the circuit. TEST the system for normal operation.
G8 CHECK FOR A SHORT TO VOLTAGE IN THE HEATED WINDSHIELD RELAY CONTROL CIRCUIT
- Ignition OFF.
- Disconnect: Right Heated Windshield Relay.
- Disconnect: GEM (Generic Electronic Module) C201A.
- Ignition ON.
- Measure the voltage between left heated windshield relay socket pin 2, circuit 31S-HB7 (BU/RD), and ground.
Is any voltage present?
Yes
REPAIR the circuit. TEST the system for normal operation.
No
GO to G9.
G9 CHECK THE HEATED WINDSHIELD RELAY CONTROL CIRCUIT FOR AN OPEN
- Measure the resistance between left heated windshield relay socket pin 2, circuit 31S-HB7 (BU/RD) and GEM (Generic Electronic Module) C201A-12, circuit 31S-HB7 (BU/RD), harness side.
Is the resistance less than 5 ohms?
Yes
GO to G15.
No
REPAIR the circuit. TEST the system for normal operation.
G10 CHECK FOR VOLTAGE AT THE INOPERATIVE HEATED WINDSHIELD DEFROST GRID
- Disconnect: Inoperative Heated Windshield Defrost Grid Power C1531 (LH) or C1532 (RH).
- Start the engine.
- Activate the heated windshield defrost switch.
- Measure the voltage between the inoperative heated windshield defrost grid C1531-1, circuit 64S-HB12 (BK/BU) (LH) or C1532-1, circuit 64S-HB25 (BK/BU) (RH), harness side and ground.
Is the voltage greater than 10 volts?
Yes
GO to G11.
No
For an inoperative LH heated windshield grid, GO to G12.
For an inoperative RH heated windshield grid, VERIFY BJB (Battery Junction Box) fuse 2 (40A) is OK. If OK, GO to G12. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Electrical Diagrams
G11 CHECK FOR GROUND AT THE INOPERATIVE HEATED WINDSHIELD DEFROST GRID
- Ignition OFF.
- Disconnect: Inoperative Rear Window Defrost Grid Ground Connector.
- Measure the resistance between the inoperative rear window defrost grid ground connector, harness side and ground.
Is the resistance less than 5 ohms?
Yes
INSTALL a new windshield. REFER to Windshield Glass . TEST the system for normal operation.
No
REPAIR the circuit. TEST the system for normal operation.
G12 CHECK THE POWER TO THE INOPERATIVE HEATED WINDSHIELD RELAY
- Ignition ON.
- Disconnect: Suspect Left or Right Heated Windshield Relay.
- For an inoperative LH heated windshield grid, measure the voltage between left heated windshield relay socket pin 1, circuit 15-HB7 (GN/BU), and ground; and between left heated windshield relay socket pin 3, circuit 30-HB8 (RD), and ground.
- For an inoperative RH heated windshield grid, measure the voltage between right heated windshield relay socket pin 1, circuit 15-HB7 (GN/BU), and ground; and between right heated windshield relay socket pin 3 and ground.
Is the voltage greater than 10 volts?
Yes
GO to G13.
No
For inoperative LH heated windshield grid, VERIFY Battery Junction Box (BJB) fuse 3 (50A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the Wiring Diagrams to identify the possible causes of the circuit short. TEST the system for normal operation. Electrical Diagrams
For inoperative RH heated windshield grid, REPAIR the circuit. TEST the system for normal operation.
G13 CHECK THE HEATED WINDSHIELD RELAY CONTROL CIRCUIT FOR AN OPEN
NOTICE: The following step uses a test light to simulate normal circuit loads. Use only the test light recommended in the Special Tools table at the beginning. 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 heated windshield defrost switch.
- For an inoperative LH heated windshield grid, connect a 12-volt incandescent test light between left heated windshield relay socket pin 1, circuit 15-HB7 (GN/BU) and left heated windshield relay socket pin 2, circuit 31S-HB7 (BU/RD).
- For an inoperative RH heated windshield grid, connect a 12-volt incandescent test light between right heated windshield relay socket pin 1, circuit 15-HB7 (GN/BU) and right heated windshield relay socket pin 2, circuit 31S-HB7 (BU/RD).
Does the test light illuminate?
Yes
GO to G14.
No
REPAIR the circuit. TEST the system for normal operation.
G14 CHECK THE SUSPECT HEATED WINDSHIELD RELAY
- Ignition OFF.
- Carry out the relay component test on the suspect heated windshield relay.
Did the heated windshield relay pass the component test?
Yes
For an inoperative LH heated windshield grid, REPAIR open in circuit 64S-HB12 (BK/BU). TEST the system for normal operation.
For an inoperative RH heated windshield grid, REPAIR open in circuit 64S-HB25 (BK/BU). TEST the system for normal operation.
No
INSTALL a new heated windshield relay. TEST the system for normal operation.
G15 CHECK FOR CORRECT GEM (Generic Electronic Module) MODULE OPERATION
- Disconnect the GEM (Generic Electronic Module) electrical connectors.
- Check for:
- corrosion.
- pushed-out pins.
- Connect the GEM (Generic Electronic Module) 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 (Generic Electronic Module). 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.