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Pinpoint Test A : The Defrost System Is Inoperative - EMTC (Electronic Manual Temperature Control): Notes

Refer to Heated Window for schematic and connector information.

Normal Operation and Fault Conditions

REFER to: Glass, Frames and Mechanisms - Vehicles With: One-Touch Open and Close Front Windows - System Operation and Component Description .

Possible Sources

Fuse(s)
Rear window defrost relay
Wiring, terminals or connectors
HVAC module
Isolator
Rear window defrost grid
BCM

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Conditions
B1013:11	Heater Rear Defog Switch: Circuit Short To Ground	This DTC sets when the BCM detects the rear window defrost switch input has been active for greater than 60 seconds.
B1013:23	Heater Rear Defog Switch: Signal Stuck Low	This DTC sets when the BCM detects the rear window defrost switch is active during self-test.
B112D:11	Rear Window Defrost LED: Circuit Short To Ground	This DTC sets when the BCM detects a short to ground on the rear window defrost LED circuit.
B112D:15	Rear Window Defrost LED: Circuit Short To Battery Or Open	This DTC sets when the BCM detects an open in the rear window defrost LED circuit.
B1C84:12	Heated Rear Window Relay Output: Circuit Short To Battery	This DTC sets when the BCM detects a short to voltage on the rear window defrost relay control circuit.
B1C84:13	Heated Rear Window Relay Output: Circuit Open	This DTC sets when the BCM detects an open in the rear window defrost relay control circuit.
B1C84:14	Heated Rear Window Relay Output: Circuit Short To Ground or Open	This DTC sets when the BCM detects a short to ground or an open in the rear window defrost relay control circuit.

Visual Inspection and Diagnostic Pre-checks

Verify BJB fuse 9 (30A) and 23 (5A) are OK.
Inspect the rear window defrost relay.
Inspect the rear window defrost grid and electrical connectors for damage.