DIAGNOSIS SYSTEM
Troubleshooting
| DESCRIPTION |
Connecting the intelligent tester to the vehicle and reading various data output from the power steering ECU assembly is the only difference between usual troubleshooting procedures and those for a vehicle with a diagnostic system.
The power steering ECU assembly records DTCs when the ECU detects a malfunction in the computer itself or in its circuits.
To check the DTCs, connect the intelligent tester to the DLC3. The intelligent tester enables you to erase the DTCs and check the freeze frame data and various forms of steering data.
| CHECK DLC3 |
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Check the DLC3.
The power steering ECU assembly uses CAN and ISO 9141-2 (Euro-OBD)/ISO 14230 (M-OBD) for communication protocol. The terminal arrangement of the DLC3 complies with ISO 15031-03 and matches the ISO 9141-2/ISO 14230 format.
Symbols (Terminal No.)
Terminal Description
Condition
Specified Condition
SIL (7) - SG (5)
Bus "+" line
During communication
Pulse generation
CG (4) - Body ground
Chassis ground
Always
Below 1 Ω
SG (5) - Body ground
Signal ground
Always
Below 1 Ω
BAT (16) - Body ground
Battery positive
Always
11 to 14 V
CANH (6) - CANL (14)
HIGH-level CAN bus line
Ignition switch off
54 to 67 Ω
CANH (6) - Battery positive
HIGH-level CAN bus line
Ignition switch off
1 MΩ or higher
CANH (6) - CG (4)
HIGH-level CAN bus line
Ignition switch off
3 kΩ or higher
CANL (14) - Battery positive
LOW-level CAN bus line
Ignition switch off
1 MΩ or higher
CANL (14) - CG (4)
LOW-level CAN bus line
Ignition switch off
3 kΩ or higher
- HINT:
- If the display shows "a communication error message" after connecting the intelligent tester cable to the DLC3 and turning the ignition switch on, there is a problem either with the vehicle or the tester.
- If communication is normal when connecting the tester to another vehicle, inspect the DLC3 on the original vehicle.
- If communication is still not possible when connecting the tester to another vehicle, the problem is probably in the tester itself. Consult the Service Department listed in the tester's operator's manual.
- If communication is normal when connecting the tester to another vehicle, inspect the DLC3 on the original vehicle.
| P/S WARNING LIGHT |
If a problem occurs in the electronic power steering system, the P/S warning light will come on in the combination meter.

