• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
BCM Fuse F9 B+ | B3794 00 B1529 00 B3922 00 | B3794 00 B1529 00 B3922 00 | -- | -- |
FRT WPR Fuse B+ | 1 | 1 | -- | -- |
Windshield Wiper Switch Signal | B3922 00 | 1 | 1 | -- |
Windshield Wiper Switch High Signal | 3 | 1 | 1 | -- |
Windshield Wiper Motor Park Switch Signal | 2 | 2 | -- | -- |
WIPER LO Relay Control | B3715 00 | 1 | 3 | -- |
WIPER HIGH Relay Control | 1 | 1 | B3875 00 | -- |
Windshield Wiper Motor High Speed Control | 1 | 1 | 1 | -- |
Windshield Wiper Motor Low Speed Control | 1 | 1 | 1 | -- |
Windshield Wiper Switch Low Reference | -- | 1 | 1 | -- |
Windshield Wiper Motor Ground | -- | 1 | -- | -- |
WIPER LO Relay Ground | -- | 1 | -- | -- |
1.Windshield wiper system malfunction 2.Wipers Do Not Park 3. Wipers Always ON |
The Body Control Module (BCM) monitors the windshield wiper/washer switch low signal circuit. When the wiper switch is placed in the low position, battery voltage is applied through the switch contacts, a series of resistors, and the wiper switch low signal circuit to the BCM. The BCM then applies battery voltage through the wiper relay control circuit to energize the WIPER LO relay. When energized, battery voltage from the FRT WPR fuse is applied through the switch side of the WIPER LO relay then through the switch side of the WIPER HIGH relay to the windshield wiper motor.
Battery voltage is between 9 and 16 Volts.
The low speed BCM output is actively being requested.
The BCM detects a short to ground or open high resistance on the BCM Fuse F9 B+ circuit.
The BCM detects a short to ground on the windshield wiper switch low speed signal circuit with wiper switch in OFF position and ignition in the OFF position.
• | The BCM will not activate the low speed output. |
• | The windshield wipers will only operate in the delay and high speed modes. |
• | The DTC will clear the current status when the condition for setting the fault is corrected. |
• | A history DTC will clear after 100 consecutive ignition cycles without a fault present. |
Wiper/Washer System Description and Operation
Control Module References for scan tool information
Ignition ON, observe the scan tool Windshield Wiper Switch parameter while rotating the wiper switch. The reading should change between Off, Intermittent, Low and High.
⇒ | If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. |
⇒ | If not the specified value, test the signal circuit terminal 7 for a short to ground. If the circuit tests normal, replace the BCM. |
⇒ | If greater than the specified range, replace the windshield wiper/washer switch. |
Important: If the switch tests open in any switch position other than Off, test the signal circuits for a short to voltage before replacing the switch.
Switch Position | Resistance |
---|---|
Off | Infinite |
Mist | 300-364 Ω |
Delay 1 | 3.48k-4.25k Ω |
Delay 2 | 2.52k-3.08k Ω |
Delay 3 | 1.78k-2.18k Ω |
Delay 4 | 1.17k-1.44k Ω |
Delay 5 | 697-851 Ω |
Low | 300-364 Ω |
High | 300-364 Ω |
⇒ | If any switch position is not within the specified range, replace the windshield wiper/washer switch. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for BCM replacement, setup, and programming |