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Home >> Mazda >> 2012 >> 6 s Touring Plus >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Wiper/Washer Systems >> On-Board Diagnostic [Auto Light/Wiper Control Module) >> DTC B1318 [Auto Light/Wiper Control Module] >> Diagnostic Procedure
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Diagnostic Procedure

Step Inspection Action
1 PERFORM PCM DTC INSPECTION 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [MZR 2.5] .)
(See DTC TABLE [MZI 3.7 V6] .)
No Go to the next step.
2 INSPECT FUSE 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Remove and inspect the following fuses:
    • MAIN 125 A fuse
    • BTN 30 A fuse
    • IG KEY1 40 A fuse
    • IG KEY2 40 A fuse
    • ROOM 15 A fuse
    • METER IG 15 A fuse
    • WIPER 25 A fuse
  • Are there any malfunction?
 Yes Replace the malfunctioning fuse, then go to Step 11.
No Go to the next step.
3 INSPECT BATTERY 
 Yes Recharge or replace the battery, then go to Step 11.
(See BATTERY RECHARGING [MZR 2.5] .)
(See BATTERY RECHARGING [MZI 3.7 V6] .)
(See BATTERY REMOVAL/INSTALLATION [MZR 2.5] .)
(See BATTERY REMOVAL/INSTALLATION [MZI 3.7 V6] .)
No Go to the next step.
4 INSPECT GENERATOR 
 Yes Replace the generator, then go to Step 11.
(See GENERATOR REMOVAL/INSTALLATION [MZR 2.5] .)
(See GENERATOR REMOVAL/INSTALLATION [MZI 3.7 V6] .)
No Go to the next step.
5 INSPECT IGNITION SWITCH CONNECTOR CONDITION 
  • Disconnect the ignition switch connector.
  • Inspect for poor connection (damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminal, then go to Step 11.
No Go to the next step.
6 INSPECT AUTO LIGHT/WIPER CONTROL MODULE CONNECTOR CONDITION 
  • Disconnect the auto light/wiper control module connector.
  • Inspect for poor connection (damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminal, then go to Step 11.
No Go to the next step.
7 INSPECT IGNITION SWITCH 
 Yes Replace the ignition switch, then go to Step 11.
(See IGNITION SWITCH REMOVAL/INSTALLATION [WITHOUT ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No Go to the next step.
8 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • Install the fuses.
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between following terminals and body ground:
    • Auto light/wiper control module terminal 2D (wiring harness-side)
    • ignition switch terminal E (wiring harness-side)
    • ignition switch terminal F (wiring harness-side)
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible short to ground or open circuit, then go to Step 11.
9 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between following terminals and body ground:
    • Ignition switch terminal B (wiring harness-side)
    • Ignition switch terminal C (wiring harness-side)
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to ground, then go to Step 11.
No Go to the next step.
10 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between following terminals:
    • Ignition switch terminal B (wiring harness-side) and auto light/wiper control module terminal 1E (wiring harness-side)
    • Ignition switch terminal C (wiring harness-side) and auto light/wiper control module terminal 2C (wiring harness-side)
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to the next step.
11 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Replace the auto light/wiper control module, then go to the next step.
(See AUTO LIGHT/WIPER CONTROL MODULE REMOVAL/INSTALLATION .)
No Go to the next step.
12 VERIFY THAT NO OTHER DTCs ARE RECORDED 
  • Are any DTCs present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [AUTO LIGHT/WIPER CONTROL MODULE] .)
No DTC troubleshooting completed.


Step Inspection Action
1 PERFORM PCM DTC INSPECTION 
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [MZR 2.5] .)
(See DTC TABLE [MZI 3.7 V6] .)
No Go to the next step.
2 INSPECT FUSE 
  • Switch the ignition to off.
  • Disconnect the negative battery cable.
  • Remove and inspect the following fuses:
    • MAIN 125 A fuse
    • BTN 30 A fuse
    • IG KEY1 40 A fuse
    • IG KEY2 40 A fuse
    • ROOM 15 A fuse
    • METER IG 15 A fuse
    • WIPER 25 A fuse
  • Are there any malfunction?
 Yes Replace the malfunctioning fuse, then go to Step 11.
No Go to the next step.
3 INSPECT BATTERY 
 Yes Recharge or replace the battery, then go to Step 11.
(See BATTERY RECHARGING [MZR 2.5] .)
(See BATTERY RECHARGING [MZI 3.7 V6] .)
(See BATTERY REMOVAL/INSTALLATION [MZR 2.5] .)
(See BATTERY REMOVAL/INSTALLATION [MZI 3.7 V6] .)
No Go to the next step.
4 INSPECT GENERATOR 
 Yes Replace the generator, then go to Step 11.
(See GENERATOR REMOVAL/INSTALLATION [MZR 2.5] .)
(See GENERATOR REMOVAL/INSTALLATION [MZI 3.7 V6] .)
No Go to the next step.
5 INSPECT RELAY BLOCK CONNECTOR CONDITION 
  • Disconnect the relay block connector.
  • Inspect for poor connection (damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminal, then go to Step 11.
No Go to the next step.
6 INSPECT AUTO LIGHT/WIPER CONTROL MODULE CONNECTOR CONDITION 
  • Disconnect the auto light/wiper control module connector.
  • Inspect for poor connection (damaged/pulled-out pins, corrosion).
  • Is there any malfunction?
 Yes Repair or replace the connector or terminal, then go to Step 11.
No Go to the next step.
7 INSPECT RELAY BLOCK 
 Yes Replace the relay block, then go to Step 11.
(See RELAY BLOCK REMOVAL/INSTALLATION [WITH ADVANCED KEYLESS ENTRY AND PUSH BUTTON START SYSTEM] .)
No Go to the next step.
8 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR SHORT TO GROUND OR OPEN CIRCUIT 
  • Install the fuses.
  • Reconnect the negative battery cable.
  • Switch the ignition to ON.
  • Measure the voltage between following terminals and body ground:
    • Auto light/wiper control module terminal 2D (wiring harness-side)
    • Relay block terminal 1A (wiring harness-side)
    • Relay block terminal 1E (wiring harness-side)
  • Is the voltage B+  ?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible short to ground or open circuit, then go to Step 11.
9 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR SHORT TO GROUND 
  • Inspect for continuity between following terminals and body ground:
    • Relay block terminal 1C (wiring harness-side)
    • Relay block terminal 1B (wiring harness-side)
  • Is there continuity?
 Yes Repair or replace the wiring harness for a possible short to ground, then go to Step 11.
No Go to the next step.
10 INSPECT AUTO LIGHT/WIPER CONTROL MODULE POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT 
  • Inspect for continuity between following terminals:
    • Relay block terminal 1C (wiring harness-side) and auto light/wiper control module terminal 1E (wiring harness-side)
    • Relay block terminal 1B (wiring harness-side) and auto light/wiper control module terminal 2C (wiring harness-side)
  • Is there continuity?
 Yes Go to the next step.
No Repair or replace the wiring harness for a possible open circuit, then go to the next step.
11 VERIFY TROUBLESHOOTING COMPLETED 
 Yes Replace the auto light/wiper control module, then go to the next step.
(See AUTO LIGHT/WIPER CONTROL MODULE REMOVAL/INSTALLATION .)
No Go to the next step.
12 VERIFY THAT NO OTHER DTCs ARE RECORDED 
  • Are any DTCs present?
 Yes Go to the applicable DTC inspection.
(See DTC TABLE [AUTO LIGHT/WIPER CONTROL MODULE] .)
No DTC troubleshooting completed.
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