• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Relay B+ Circuit | 2 | 2 | -- | -- |
Rear Defog Relay Control | B0283 | B0283 | B0283 | -- |
Rear Defogger Control Circuit | 2 | 2 | 1 | -- |
HVAC Class 2 Serial Data | 2 | 2 | 2 | -- |
Rear Window Defogger Grid Ground | -- | 2 | 2 | -- |
1. Rear defogger always ON 2. Rear defogger inoperative |
The body control module (BCM) monitors the voltage level on the supply voltage circuit of the R/DEFOG relay. The voltage level should be low while the R/DEFOG relay is de-energized. The voltage will be near system voltage when the BCM energizes the R/DEFOG relay.
Battery voltage must be between 9-16 volts.
The DTC will set when the BCM detects a fault in the Rear Defog Relay Control circuit for 1 second or greater.
• | The BCM stores the DTC to memory. |
• | The rear window defogger will not operate. |
• | This DTC will change from current to history when the fault is no longer present. |
• | A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present. |
• | The technician issues a scan tool CLEAR DTCs command. |
Stationary Windows Connector End Views
Rear Window Defogger Description and Operation
Ignition ON, command the rear window defogger ON and OFF with a scan tool. Observe the rear window defogger operation as the rear window defogger turns ON and OFF.
⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM. |
⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM. |
⇒ | If the resistance is not within the specified range, replace the relay. |
• | 30 and 86 |
• | 30 and 87 |
• | 30 and 85 |
• | 85 and 87 |
⇒ | If greater than the specified range, replace the relay. |
⇒ | If greater than the specified range, replace the relay |