HICAS Diagnostics |
Source: TTZs of Dallas
|
Turbos come standard with High Capacity Actively Controlled Suspension, a fancy way to say 4 wheel steering. There's a visual diagnostic mode to check for problems in the HICAS functions.
The '89 - '93 TTs have hydraulic HICAS running off the power steering pump, where '94+ utilises electric actuators to handle the rear steering chores. Their codes are a little different, but the procedure is the same. It might require a few tries to make it work.
The '89 - '93 TTs have hydraulic HICAS running off the power steering pump, where '94+ utilises electric actuators to handle the rear steering chores. Their codes are a little different, but the procedure is the same. It might require a few tries to make it work.
Fig 1.
Procedure
- Turn key switch “OFF”.
- Set shift lever to “P" position (A/T model) or “Neutral” position (M/T model).
- Turn ignition switch “ON”.
- Immediately start engine.
- Turn steering wheel from left to right (at least 20° from the neutral position) 5 times or more, then depress foot brake pedal at least 5 times all within 10 seconds after ignition switch has been turned “ON”.
- Turn steering wheel to a point approximately 30° from the neutral position, then set steering wheel back to the neutral position and check to ensure that rear wheels turn to the left and right alternately.
- Drive the car forward 15 feet under 9mph to enter the full diagnostic mode.
- The HICAS dash light will flash a code indicating any problems. Long flash is first digit, short flash is 2nd digit.
- Diagnostic mode is exited when: ignition is turned off, vehicle speed exceeds 9mph or diagnostic mode has been active for 5 minutes.
HICAS light codes for '89 - '93
1. HICAS solenoid R.H.
2. HICAS solenoid L.H.
3. Cut-off valve
4. Power Steering solenoid
5. Vehicle Speed sensor
6. Steering angle sensor
7. Steering Neutral positon sensor
8. A/T: Parking Brake Sensor M/T: Clutch sensor
9. A/T: Inhibitor sensor M/T: Neutral sensor
1. HICAS solenoid R.H.
2. HICAS solenoid L.H.
3. Cut-off valve
4. Power Steering solenoid
5. Vehicle Speed sensor
6. Steering angle sensor
7. Steering Neutral positon sensor
8. A/T: Parking Brake Sensor M/T: Clutch sensor
9. A/T: Inhibitor sensor M/T: Neutral sensor
HICAS light codes for '94 - '99
11. HICAS control unit
12. HICAS motor power supply not present
13. HICAS motor output not present
21. Vehicle speed signal not present
22. Steering angle sensor angle signal not present
23. Steering angle sensor neutral not present
24. Rear main sensor input not present
25. Rear sub sensor input not present
31. Parking brake sensor input not present
32. Inhibitor switch (A/T) or neutral switch (M/T) input not present
33. Engine speed signal not present
11. HICAS control unit
12. HICAS motor power supply not present
13. HICAS motor output not present
21. Vehicle speed signal not present
22. Steering angle sensor angle signal not present
23. Steering angle sensor neutral not present
24. Rear main sensor input not present
25. Rear sub sensor input not present
31. Parking brake sensor input not present
32. Inhibitor switch (A/T) or neutral switch (M/T) input not present
33. Engine speed signal not present
