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Wiper / Washer (Diagnostics): Diagnosis Lexus RX III

Wiper/washer Systems 4 illustrations ~1199 words

HOW TO PROCEED WITH TROUBLESHOOTING

HINT

Use the following procedure to troubleshoot the wiper and washer system.

  1. VEHICLE BROUGHT TO WORKSHOP NEXT: Go to next step
  2. CUSTOMER PROBLEM ANALYSIS AND SYMPTOM CHECK NEXT: Go to next step
  3. INSPECT BATTERY VOLTAGE Standard Voltage 11 to 14 V If the voltage is below 11 V, recharge or replace the battery before proceeding to the next step. NEXT: Go to next step
  4. PROBLEM SYMPTOMS TABLE Result Result Proceed to Fault is not listed in problem symptoms table A Fault is listed in problem symptoms table B B --> Go to 6 step 6 A: Go to next step
  5. OVERALL ANALYSIS AND TROUBLESHOOTING Terminals of ECU. Refer to «TERMINALS OF ECU»(ref-400840-S14245703292011051800000) Fail-safe chart. Refer to «FAIL-SAFE CHART»(ref-400840-S07871253372011051800000) Inspection On-vehicle inspection NEXT: Go to next step
  6. ADJUST, REPAIR OR REPLACE NEXT: Go to next step
  7. CONFIRMATION TEST NEXT --> END

PROBLEM SYMPTOMS TABLE

HINT

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

SymptomSuspected AreaSee
Front wipers do not operate at allWiper ECU power source circuitRefer to Wiper ECU Power Source Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in LOFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in HIFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front washer motor does not operateWasher motor circuitRefer to Washer Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Washer fluid does not flowWasher hose and nozzle
Front wipers do not operate when front washer switch is onFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
When the front wiper switch is off, the wiper blades do not park or park in the wrong positionFront wiper arm installation positionRefer to INSTALLATION
Windshield wiper motor assemblyRefer to REMOVAL (TO 8/2009)

FRONT WIPER AND WASHER (W/O AUTO WIPER SYSTEM)

SymptomSuspected AreaSee
Front wipers do not operate at allWiper ECU power source circuitRefer to Wiper ECU Power Source Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in AUTORain sensor tape*1
Rain sensor circuitRefer to Rain Sensor Circuit
Speed signal circuitRefer to Speed Signal Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in LOFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in HIFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front washer motor does not operateWasher motor circuitRefer to Washer Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Washer fluid does not flowWasher hose and nozzle
Front wipers do not operate when front washer switch is onFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
When the front wiper switch is off, the wiper blades do not park or park in the wrong positionFront wiper arm installation positionRefer to INSTALLATION
Windshield wiper motor assemblyRefer to REMOVAL (TO 8/2009)

FRONT WIPER AND WASHER (W/ AUTO WIPER SYSTEM)

HINT

*1: Before inspecting the rain sensor, first check if the rain sensor tape is correctly installed.

SymptomSuspected AreaSee
Rear wiper does not operate at allRR WIP fuse
Rear wiper motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Rear wiper does not operate in LO or HIRear wiper motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Rear washer motor does not operateRR WASH fuse
Rear washer motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Washer fluid does not flowWasher hose and nozzle
When the rear wiper switch is off, the wiper blade does not park or park in the wrong positionRear wiper arm installation positionRefer to INSTALLATION
Rear wiper motor assemblyRefer to INSPECTION

REAR WIPER AND WASHER

SymptomSuspected AreaSee
Headlight cleaner system does not operate when the headlight cleaner switch is operated.IG power source circuitRefer to IG Power Source Circuit
Headlight cleaner switch circuitRefer to Headlight Cleaner Switch Circuit
Headlight cleaner motor and relay circuitRefer to Headlight Cleaner Motor and Relay Circuit
Headlight cleaner control relayRefer to REMOVAL
Headlight cleaner system does not operate when the front washer switch is operated*2.IG power source circuitRefer to IG Power Source Circuit
Headlight signal circuitRefer to Headlight Signal Circuit
Washer signal circuitRefer to Washer Signal Circuit
Headlight cleaner motor and relay circuitRefer to Headlight Cleaner Motor and Relay Circuit
Headlight cleaner control relayRefer to REMOVAL

HEADLIGHT CLEANER SYSTEM

SymptomSuspected AreaSee
Washer fluid level warning system does not operateWasher fluid level warning switch circuitRefer to Washer Fluid Level Warning Switch Circuit
Combination meter assemblyRefer to REMOVAL (TO 8/2009)

WASHER FLUID LEVEL WARNING SYSTEM

HINT

Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspected areas in the order they are listed. Replace parts as necessary.

SymptomSuspected AreaSee
Front wipers do not operate at allWiper ECU power source circuitRefer to Wiper ECU Power Source Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in LOFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in HIFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front washer motor does not operateWasher motor circuitRefer to Washer Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Washer fluid does not flowWasher hose and nozzle
Front wipers do not operate when front washer switch is onFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
When the front wiper switch is off, the wiper blades do not park or park in the wrong positionFront wiper arm installation positionRefer to INSTALLATION
Windshield wiper motor assemblyRefer to REMOVAL (TO 8/2009)

FRONT WIPER AND WASHER (W/O AUTO WIPER SYSTEM)

SymptomSuspected AreaSee
Front wipers do not operate at allWiper ECU power source circuitRefer to Wiper ECU Power Source Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in AUTORain sensor tape*1
Rain sensor circuitRefer to Rain Sensor Circuit
Speed signal circuitRefer to Speed Signal Circuit
Front wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in LOFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front wipers do not operate in HIFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Front washer motor does not operateWasher motor circuitRefer to Washer Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
Washer fluid does not flowWasher hose and nozzle
Front wipers do not operate when front washer switch is onFront wiper motor circuitRefer to Front Wiper Motor Circuit
Windshield wiper switch assemblyRefer to REMOVAL (TO 8/2009)
When the front wiper switch is off, the wiper blades do not park or park in the wrong positionFront wiper arm installation positionRefer to INSTALLATION
Windshield wiper motor assemblyRefer to REMOVAL

FRONT WIPER AND WASHER (W/ AUTO WIPER SYSTEM)

HINT

*1: Before inspecting the rain sensor, first check if the rain sensor tape is correctly installed.

SymptomSuspected AreaSee
Rear wiper does not operate at allRR WIP fuse
Rear wiper motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Rear wiper does not operate in LO or HIRear wiper motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Rear washer motor does not operateRR WASH fuse
Rear washer motor assemblyRefer to INSPECTION
Windshield wiper switch assemblyRefer to INSPECTION
Harness or connector
Washer fluid does not flowWasher hose and nozzle
When the rear wiper switch is off, the wiper blade does not park or park in the wrong positionRear wiper arm installation positionRefer to INSTALLATION
Rear wiper motor assemblyRefer to INSPECTION

REAR WIPER AND WASHER

SymptomSuspected AreaSee
Headlight cleaner system does not operate when the headlight cleaner switch is operated.IG power source circuitRefer to IG Power Source Circuit
Headlight cleaner switch circuitRefer to Headlight Cleaner Switch Circuit
Headlight cleaner motor and relay circuitRefer to Headlight Cleaner Motor and Relay Circuit
Headlight cleaner control relayRefer to REMOVAL
Headlight cleaner system does not operate when the front washer switch is operated*2.IG power source circuitRefer to IG Power Source Circuit
Headlight signal circuitRefer to Headlight Signal Circuit
Washer signal circuitRefer to Washer Signal Circuit
Headlight cleaner motor and relay circuitRefer to Headlight Cleaner Motor and Relay Circuit
Headlight cleaner control relayRefer to REMOVAL

HEADLIGHT CLEANER SYSTEM

SymptomSuspected AreaSee
Washer fluid level warning system does not operateWasher fluid level warning switch circuitRefer to Washer Fluid Level Warning Switch Circuit
Combination meter assemblyRefer to REMOVAL (TO 8/2009)

WASHER FLUID LEVEL WARNING SYSTEM

Scheme 155

Scheme 155: TERMINALS OF ECU

Scheme 156

Scheme 156

Scheme 157

Scheme 157
  1. CHECK WINDSHIELD WIPER SWITCH ASSEMBLY Disconnect the F42 windshield wiper switch assembly connector. Measure the voltage and resistance according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition F42-1 (EW) - Body ground W-B - Body ground Body ground Always Below 1 ohms F42-3 (WIG)*1 - Body ground R - Body ground Power source circuit Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V F42-17 (+B) - Body ground L - Body ground Power source circuit Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V HINT: *1: w/ Auto Wiper System If the result is not as specified, there may be a malfunction in the wire harness. Reconnect the F42 windshield wiper switch assembly connector. Measure the voltage according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition F42-2 (WF) - Body ground B - Body ground Front washer motor circuit Front washer switch on Below 1 V Front washer switch off 11 to 14 V F42-5 (MPX1)*1 - Body ground V - Body ground Rain sensor signal Engine switch on (IG) Pulse generation F42-6 (SPD)*1 - Body ground GR - Body ground Speed signal Driving at approx. 20 km/h (12 mph) Pulse generation F42-7 (TAIL)*1 - Body ground L - Body ground Light control switch tail position signal circuit Light control switch in tail position 11 to 14 V Light control switch off Below 1 V F42-8 (+1) - Body ground SB - Body ground Front wiper motor LO speed signal circuit Front wiper motor in LO operation 11 to 14 V Front wiper motor off Below 1 V F42-9 (+2) - Body ground GR - Body ground Front wiper motor HI speed signal circuit Front wiper motor in HI operation 11 to 14 V Front wiper motor off Below 1 V F42-18 (+S) - Body ground R - Body ground Front wiper motor operation signal Front wiper motor operates 11 to 14 V Front wiper motor off Below 1 V HINT: *1: w/ Auto Wiper System If the result is not as specified, the windshield wiper relay assembly may have a malfunction.
  2. CHECK MAP LIGHT ASSEMBLY Disconnect the T10 map light assembly connector. Measure the voltage and resistance according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition T10-26 (IG) - Body ground P - Body ground Power source circuit Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V T10-40 (GND) - Body ground W - Body ground Body ground Always Below 1 ohms If the result is not as specified, there may be a malfunction in the wire harness. Reconnect the T10 map light assembly connector. Measure the voltage according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition T10-24 (IG2) - T10-19 (GND2) G - W-B Power source circuit Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V If the result is not as specified, the map light assembly may have a malfunction.
  3. CHECK HEADLIGHT CLEANER CONTROL RELAY Disconnect the A33 headlight cleaner control relay connector. Measure the voltage and resistance according to the value(s) in the table below. Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition A33-1 (HDLO) - A33-4 (E) L - W-B Low beam headlight signal Light control switch in head position Below 1 V Light control switch off 11 to 14 V A33-2 (H) - A33-4 (E) W - W-B Headlight cleaner switch operation signal Headlight cleaner switch off 11 to 14 V Headlight cleaner switch on Below 1 V A33-3 (IG) - A33-4 (E) BR - W-B Engine switch on (IG) signal (Power source circuit) Engine switch off Below 1 V Engine switch on (IG) 11 to 14 V A33-4 (E) - Body ground W-B - Body ground Body ground Always Below 1 ohms A33-5 (FRWA) - A33-4 (E) P - W-B Front washer switch signal Front washer switch off 11 to 14 V Front washer switch on Below 1 V If the result is not as specified, there may be a malfunction in the wire harness.

INSPECTION PROCEDURE

Note. First check that the low beam headlights operate normally.

Scheme 158

Scheme 158: PROCEDURE
  1. CHECK HARNESS AND CONNECTOR (LOW BEAM HEADLIGHT RELAY - ECU) Disconnect the A33 headlight cleaner control relay connector. Measure the voltage according to the value(s) in the table below. Standard Voltage Tester Connection Switch Condition Specified Condition A33-1 (HDLO) - Body ground Light control switch in head position 11 to 14 V Light control switch off Below 1 V TEXT IN ILLUSTRATION *1 Front view of wire harness connector (to Headlight Cleaner Control Relay) NG --> REPAIR OR REPLACE HARNESS OR CONNECTOR OK --> See step 2
  2. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to «PROBLEM SYMPTOMS TABLE»(ref-400840-S24523419422011051800000)

Note. First check that the low beam headlights operate normally.