Diagnostic procedure

WARNING: This page is about a different car, the 2005 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

DTC B1342 DIAGNOSTIC PROCEDURE

STEP	INSPECTION		ACTION
1	INSPECT FUSE Inspect EPS 60 A fuse. Is EPS 60 A fuse normal?	Yes	Go to the next step.
1		No	Replace EPS 60 A fuse, then go to Step 10.
2	INSPECT WHETHER MALFUNCTION IS CAUSED BY POOR CONNECTION OF EPS CONTROL MODULE OR PIN DEFORMATION Turn the ignition switch off. Inspect connection of the EPS control module and wiring harness. Disconnect the EPS control module connector. Inspect whether malfunction is caused by bent or poorly connected EPS control module connector pin. Are connection and pin of connector and wiring harness normal?	Yes	Go to the next step.
2		No	Repair or replace faulty connector harness, then go to Step 6.
3	INSPECT EPS MOTOR POWER SUPPLY CIRCUIT FOR OPEN CIRCUIT Disconnect the battery positive terminal. Inspect for continuity between EPS control module terminal 1A and battery positive terminal. Is there continuity?	Yes	Go to the next step.
3		No	Repair or replace the wiring harness for open circuit between the EPS control module and battery, then go to Step 10.
4	INSPECT EPS MOTOR POWER SUPPLY CIRCUIT FOR SHORT TO GROUND Inspect for continuity between EPS control module terminal 1A and ground. Is there continuity?	Yes	Repair or replace the wiring harness for short to ground between the EPS control module and battery, then go to Step 10.
4		No	Go to the next step.
5	INSPECT EPS MOTOR CIRCUIT FOR OPEN CIRCUIT Disconnect the noise filter connector. Inspect for continuity between the EPS control module terminals and noise filter terminals. EPS control module terminal 4A-noise filter terminal a. EPS control module terminal 4B-noise filter terminal b. Is there continuity?	Yes	Go to the next step.
5		No	Replace the noise filter, then go to Step 10.
6	INSPECT EPS MOTOR CIRCUIT FOR OPEN CIRCUIT Disconnect the EPS motor connector. Inspect for continuity between the EPS motor terminals and noise filter terminals. EPS motor terminal A-noise filter terminal a. EPS motor terminal B-noise filter terminal b. Is there continuity?	Yes	Go to the next step.
6		No	Repair or replace the wiring harness for open circuit between the EPS motor and noise filter, then go to Step 10.
7	INSPECT EPS MOTOR CIRCUIT FOR SHORT TO POWER Measure the voltage between the EPS motor terminals and ground. EPS motor terminal A-ground EPS motor terminal B-ground Is there any B+?	Yes	Repair or replace the wiring harness for short to power between the EPS motor and noise filter, then go to Step 10.
7		No	Go to the next step.
8	INSPECT EPS MOTOR CIRCUIT FOR SHORT TO GROUND Inspect for continuity between the EPS motor terminals and ground. EPS motor terminal A-ground EPS motor terminal B-ground Is there continuity?	Yes	Repair or replace the wiring harness for short to ground between the EPS motor and noise filter, then go to Step 10.
8		No	Go to the next step.
9	INSPECT EPS MOTOR GROUND CIRCUIT FOR OPEN CIRCUIT Disconnect the battery negative terminal. Measure continuity between EPS control module terminal 1B and battery negative terminal. Is there continuity?	Yes	Go to the next step.
9		No	Repair or replace the wiring harness for open circuit between the EPS control module and battery, then go to the next step.
10	VERIFY TROUBLESHOOTING COMPLETED Make sure to reconnect all disconnected connectors. Clear the DTC from the memory. (See CLEARING DTCS PROCEDURE .) Turn the ignition switch off. Start the engine. Is the same DTC present?	Yes	Replace the EPS control module and/or steering gear and linkage, then go to the next step. (See EPS CONTROL MODULE REMOVAL/INSTALLATION .) (See STEERING GEAR AND LINKAGE REMOVAL/INSTALLATION .)
10		No	Go to the next step.
11	VERIFY AFTER REPAIR PROCEDURE Are any other DTCs present?	Yes	Go to the applicable DTC inspection. (See DTC TABLE .)
11	VERIFY AFTER REPAIR PROCEDURE Are any other DTCs present?	No	DTC troubleshooting completed.