Component Tests and General Diagnostics

INSPECTION

NOTICE:
- When jacking or lifting up vehicles which have air suspension and running the engine, connect terminals TD and E1 of DLC 2 before starting the inspection.
- When replacing Progressive Power Steering (PPS) ECU, be careful not to also replace tilt and telescopic ECU.






1. Inspect ECU-IG fuse (Instrument panel J/B).
2. Inspect PPS ECU circuit.
a. Disconnect the PPS ECU connector.
b. Inspect the connector on wire harness side, as shown in the illustration.
If the circuit is not as specified, check and replace the wire harness.
If the circuit is not as specified, inspect the speed sensor.





3. Inspect PPS solenoid valve.
a. Disconnect the PPS solenoid connector.
b. Measure the resistance between the terminals of the solenoid 1 and 2.
Resistance: 6-11 ohms
If it is not as specified, replace the pressure control valve with the solenoid valve.





c. Check the PPS solenoid operation.
(1) Connect the battery positive terminal to the solenoid terminal 1.
(2) Connect the battery negative terminal to the solenoid terminal 2.
(3) Check that the solenoid makes a "clicks" sound.
If it is faulty, replace the pressure control valve with the solenoid valve.

NOTICE:
- Do not apply voltage for more than 30 seconds to avoid burning out the solenoid.
- If repeating this step, wait until the solenoid cools down enough that it can be touched by hand.

d. Connect the PPS solenoid connector.





e. Inspect the PPS solenoid valve circuit.
(1) Disconnect the PPS ECU connector.
(2) Check continuity between the terminals of the connector on wire harness side.
Tester connection:
1-6
Specified condition: No continuity
2-6
Specified condition: No continuity
If it is not as specified, repair or replace wire harness or connector.
(3) Connect the PPS ECU connector.





4. Inspect PPS ECU.
a. Jack up the vehicle and support it on stands.
b. Start the engine.
c. Measure the voltage of ECU.
(1) Using a voltmeter, measure the voltage between ECU terminals 2 and 6 while the engine is idling.
Standard voltage: 0.33-0.43 volts.





(2) Place the transmission in gear and while running at about 62 mph (100 km/h) measure the voltage between ECU terminals 2 and 6.
Standard voltage: 0.12-0.25 volts
If no voltage, try another ECU.
d. Lower vehicle.