Pinpoint Test I : One Or More Rear Wiper Modes Are Inoperative
WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
- I1 CHECK THE MULTIFUNCTION SWITCH PIDs
- Ignition ON.
- Using a diagnostic scan tool, view the SCCM PIDs.
- Using a diagnostic scan tool, monitor the following SCCM PIDs :
- Rear Wiper Delay 1 (R_WIPE_DEL1)
- Rear Wiper Delay 2 (R_WIPE_DEL2)
- Place the rear window wiper switch to the INT 1 and then INT 2 setting.
Do the PIDs correspond correctly with the wiper/washer switch settings?
Yes GO to I2. No INSTALL a new multifunction switch. REFER to Steering Column Switches . If the concern is still present, INSTALL a new SCCM. REFER to Steering Column Switches . - I2 CHECK THE REAR WINDOW WIPER MOTOR RELAY
- Ignition OFF.
- Disconnect: Rear Window Wiper Motor Relay.
- Substitute a known good relay.
- Ignition ON.
- Recheck the rear window wiper operation.
- Ignition OFF.
Does the rear window wiper operate?
Yes REMOVE the known good relay. INSTALL a new rear window wiper motor relay. No REMOVE the known good relay. GO to I3. - I3 CHECK THE REAR WINDOW WIPER MOTOR RELAY BATTERY SUPPLIED VOLTAGE CIRCUIT FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead Rear window wiper motor relay, cavity 3 Ground
Is the voltage greater than 11 volts?
Yes GO to I4. No VERIFY the BJB fuse 47 (30A) is OK. If OK, REPAIR the circuit. If not OK, REFER to the OEM Electrical Wiring Diagram Introduction to identify the possible causes of the circuit short. - Measure:
- I4 CHECK THE REAR WINDOW WIPER MOTOR RELAY COIL VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead Rear window wiper motor relay, cavity 1 Ground
Is the voltage greater than 11 volts?
Yes GO to I5. No REPAIR the circuit. - I5 CHECK THE REAR WINDOW WIPER MOTOR RELAY GROUND CIRCUIT FOR AN OPEN
- Measure:
Positive Lead Measurement / Action Negative Lead Rear window wiper motor relay, cavity 1 Rear window wiper motor relay, cavity 2
Is the voltage greater than 11 volts?
Yes GO to I6. No REPAIR the circuit. - Measure:
- I6 CHECK THE REAR WINDOW WIPER MOTOR VOLTAGE SUPPLY CIRCUIT FOR AN OPEN
- Ignition OFF.
- Connect: Rear Window Wiper Motor Relay.
- Disconnect: Rear Window Wiper Motor C476 .
- Ignition ON.
- Measure:
Positive Lead Measurement / Action Negative Lead C476-1 Ground
Is the voltage greater than 11 volts?
Yes GO to I7. No REPAIR the circuit. - I7 CHECK THE REAR WINDOW WIPER MOTOR GROUND CIRCUIT FOR AN OPEN
Is the voltage greater than 11 volts?
Yes GO to I8. No REPAIR the circuit. - I8 CHECK THE WINDSHIELD WIPER MOTOR CONTROLNOTE: The following step uses a test lamp to simulate normal circuit loads. Use only a Rotunda Test Lamp (SGT27000) or 250- 300mA incandescent bulb test lamp. To avoid connector terminal damage, use the Rotunda Flex Probe kit for the test lamp probe connection to the vehicle. Do not use the test lamp probe directly on any connector.
- Ignition OFF.
- Ignition ON.
- Place the rear window wiper switch to the INT 2 setting and observe the test lamp for 30 seconds.
Does the test lamp flash on and off at a regular interval?
Yes INSTALL a new rear window wiper motor. REFER to Wiper Motor - Rear Window . No GO to I9. - I9 CHECK THE REAR WINDOW WIPER MOTOR CONTROL CIRCUIT FOR AN OPEN
- Ignition OFF.
- Connect: Rear Window Wiper Motor C476 .
- Disconnect: Windshield Wiper Motor C1656 .
- Connect:
Lead 1 Measurement / Action Lead 2 C1656-11 Ground
- Ignition ON.
Does the rear window wiper motor operate?
Yes REMOVE the jumper wire. INSTALL a new windshield wiper motor. REFER to Wiper Motor - Windshield . No REMOVE the jumper wire. REPAIR the circuit.