Honda Civic. Manual — part 512

Fig. 26: Measuring Voltage Between Body Ground And EPS Control Unit
Connector B (2P) No. 1 Terminal

Fig. 27: Measuring Voltage Between Connector C (2P) No. 1 Terminal
And Connector C (2P) Non Terminal

Is there battery voltage?

YES -Go to step 9.

NO -Check for loose terminals in the EPS control unit connectors and motor
connectors, and repair if necessary. If no poor connections are found, replace
the EPS control unit (see EPS CONTROL UNIT
REMOVAL/INSTALLATION ).

9. Turn the ignition switch to LOCK (0).

10. Disconnect the motor 1P connector and motor 2P connector.
11. Turn the ignition switch ON (II).
12. Measure voltage between body ground and EPS control unit connector B (2P)

No. 1 terminal, connector C (2P) No. 1 terminal, and connector C (2P) No. 2

2008 Honda Civic EX

2006-08 STEERING EPS System - Civic (All Except Hybrid & Si)

terminal individually.

Fig. 28: Measuring Voltage Between Body Ground And EPS Control Unit
Connector B (2P) No. 1 Terminal

Fig. 29: Measuring Voltage Between Connector C (2P) No. 1 Terminal
And Connector C (2P) No. 2 Terminal

Is there battery voltage?

YES - Repair short to power in the wire between the EPS control unit and
motor.

NO - Short to power in the motor wire harness, or motor internal circuit,
replace the motor (see MOTOR REMOVAL AND INSTALLATION ).

DTC 34-01: POWER RELAY STUCK ON (IGNITION SWITCH IS OFF)

1. Clear the DTC with the HDS.
2. Turn the ignition switch to LOCK (0).
3. Turn the ignition switch ON (II).

2008 Honda Civic EX

2006-08 STEERING EPS System - Civic (All Except Hybrid & Si)

Does the EPS indicator come on?

YES - Go to step 4.

NO - Check for loose terminals or poor connections. If the connections are
good, the system is OK at this time.

4. Check for DTCs with the HDS.

Is DTC 34-01 indicated?

YES -Check for loose terminals in the EPS control unit connectors, and repair
if necessary. If no poor connections are found, replace the EPS control unit
(see EPS CONTROL UNIT REMOVAL/INSTALLATION ).

NO -Troubleshoot the indicated DTC. If there are no DTCs, the system is OK
at this time.

DTC 34-02: FAIL-SAFE RELAY STUCK ON (INITIAL DIAGNOSIS)

1. Clear the DTC with the HDS.
2. Turn the ignition switch to LOCK (0).
3. Turn the ignition switch ON (II).

Does the EPS indicator come on?

YES -Go to step 4.

NO -Check for loose terminals or poor connections. If the connections are
good, the system is OK at this time.

4. Check for DTCs with the HDS.

Is DTC 34-02 indicated?

YES -Go to step 5.

NO -Troubleshoot the indicated DTC. If there are no DTCs, the system is OK

2008 Honda Civic EX

2006-08 STEERING EPS System - Civic (All Except Hybrid & Si)

at this time.

5. Turn the ignition switch to LOCK (0).
6. Disconnect EPS control unit connector B (2P) and connector C (2P).
7. Turn the ignition switch ON (II).
8. Measure voltage between body ground and EPS control unit connector B (2P)

No. 1 terminal, connector C (2P) No. 1 terminal, and connector C (2P) No. 2
terminal individually.

Fig. 30: Measuring Voltage Between Body Ground And EPS Control Unit
Connector B (2P) No. 1 Terminal

Fig. 31: Measuring Voltage Between Connector C (2P) No. 1 Terminal
And Connector C (2P) No. 2 Terminal

Is there battery voltage?

YES -Repair short to power in the wire between the EPS control unit and the
motor.

2008 Honda Civic EX

2006-08 STEERING EPS System - Civic (All Except Hybrid & Si)