ATP Switch
ATP SwitchCONSULT-II REFERENCE VALUE IN DATA MONITOR MODE:
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE:
CAUTION: When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
DIAGNOSTIC PROCEDURE
1. CHECK ATP SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select "DATA MONITOR" mode for "ALL MODE AWD/4WD" with CONSULT-II.
3. Read out the value of "ATP SWITCH".
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector terminal and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND ATP SWITCH
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the ATP switch harness connector.
3. Check continuity between transfer control unit harness connector E143 terminal 40 and ATP switch harness connector F55 terminal 8.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK GROUND CIRCUIT
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Check continuity between ATP switch harness connector F55 terminal 9 and ground.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 4.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
4. CHECK ATP SWITCH
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect ATP switch harness connector.
3. Remove ATP switch.
4. Push and release ATP switch and check continuity between ATP switch terminals 8 and 9.
OK or NG
OK >> GO TO 5.
NG >> Replace ATP switch.
5. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "Transfer Control Unit Input/Output Signal Reference Values". Transfer Control Unit Input/Output Signal Reference Values
OK or NG
OK >> GO TO 6.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.
6. CHECK ATP WARNING LAMP
1. Turn ignition switch "ON". (Do not start engine.)
2. Move A/T selector lever to "P" position.
3. Set 4WD shift switch from "4H" to "4LO" or "4LO" to "4H".
Does ATP warning lamp turn ON while switching?
YES >> GO TO TF-124, "ATP Warning Lamp Turns ON". ATP Warning Lamp Turns On
NO >> Inspection End.
COMPONENT INSPECTION
1. Turn ignition switch "OFF". (Stay for at least 5 second.)
2. Disconnect ATP switch harness connector.
3. Remove ATP switch.
4. Push and release ATP switch and check continuity between ATP switch terminals 8 and 9.
5. If NG, replace the ATP switch.