Mazda DTC P0758 Diagnostic

DTC P0758	Shift solenoid B malfunction (electrical)
DETECTION CONDITION	• If the PCM detects either of the following conditions, the PCM determines that shift solenoid B circuit has a malfunction. – Shift solenoid B voltage stuck at B+ after engine start – Shift solenoid B voltage stuck at 0 V after engine start Diagnostic support note: • This is a continuous monitor (CCM). • The MIL illuminates if the PCM detects the above malfunction conditions during the first drive cycle. • A PENDING CODE is not available. • FREEZE FRAME DATA is available. • The AT warning light illuminates. • The DTC is stored in the PCM memory.
POSSIBLE CAUSE	• Shift solenoid B malfunction • Short to ground in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF) • Short to power supply in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF) • Open circuit in wiring harness between shift solenoid B terminal B and ATX terminal C • Open circuit in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF) • Open circuit in wiring harness between shift solenoid B terminal A and body ground • Damaged connector between shift solenoid B and PCM • PCM malfunction

DTC P0758

Shift solenoid B malfunction (electrical)

DETECTION CONDITION

• If the PCM detects either of the following conditions, the PCM determines that shift solenoid B circuit has a malfunction.

– Shift solenoid B voltage stuck at B+ after engine start

– Shift solenoid B voltage stuck at 0 V after engine start

Diagnostic support note:

• This is a continuous monitor (CCM).

• The MIL illuminates if the PCM detects the above malfunction conditions during the first drive cycle.

• A PENDING CODE is not available.

• FREEZE FRAME DATA is available.

• The AT warning light illuminates.

• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Shift solenoid B malfunction

• Short to ground in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF)

• Short to power supply in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF)

• Open circuit in wiring harness between shift solenoid B terminal B and ATX terminal C

• Open circuit in wiring harness between ATX terminal C and PCM terminal 1BH (Z6)/1C (LF)

• Open circuit in wiring harness between shift solenoid B terminal A and body ground

• Damaged connector between shift solenoid B and PCM

• PCM malfunction

Diagnostic procedure


STEP	INSPECTION		ACTION
1	VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has the FREEZE FRAME DATA been recorded?	Yes	Go to the next step.
1		No	Record the FREEZE FRAME DATA on the repair order, then go to the next step.
2	VERIFY RELATED REPAIR INFORMATION AVAILABILITY • Verify related Service Bulletins and/or on-line repair information availability. • Is any related repair information available?	Yes	Perform repair or diagnosis according to the available repair information. • If the vehicle is not repaired, go to the next step.
2		No	Go to the next step.
3	INSPECT ATX CONNECTOR FOR POOR CONNECTION • Turn the ignition switch to the LOCK position. • Disconnect the ATX connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal?	Yes	Go to the next step.
3		No	Repair or replace the connector and/or terminals, then go to Step 11.
4	INSPECT RESISTANCE • Inspect the resistance between ATX terminal C (transaxle case side) and body ground. • Is the resistance within 1.0-4.2 ohms?	Yes	Go to Step 7.
4		No	Go to the next step.
5	INSPECT SHIFT SOLENOID B CONNECTOR FOR POOR CONNECTION • Disconnect the shift solenoid B connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal?	Yes	Go to the next step.
5		No	Repair or replace the connector and/or terminals, then go to Step 11.
6	INSPECT RESISTANCE • Inspect the resistance between shift solenoid B terminals A and B (part-side). • Is the resistance within 1.0-4.2 ohms?	Yes	Replace the solenoid wiring harness, then go to Step 11.
6		No	Verify shift solenoid B installation. • If solenoid installed correctly, replace the solenoid, then go to Step 11.
7	INSPECT PCM CONNECTOR FOR POOR CONNECTION • Disconnect the PCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal?	Yes	Go to the next step.
7		No	Repair or replace the connector and/or terminals, then go to Step 11.
8	INSPECT ATX CONNECTOR CIRCUIT FOR OPEN CIRCUIT • Inspect for continuity between PCM terminal 1BH (Z6)/1C (LF) (wiring harness-side) and ATX terminal C (wiring harness-side). • Is there continuity between terminals?	Yes	Go to the next step.
8		No	Repair or replace the wiring harness, then go to Step 11.
9	INSPECT ATX CONNECTOR CIRCUIT FOR SHORT TO POWER SUPPLY • Turn the ignition switch to the ON position (engine off). • Inspect for voltage at ATX terminal C (wiring harness-side). • Is the voltage 0 V?	Yes	Go to the next step.
9		No	Repair or replace the wiring harness, then go to Step 11.
10	INSPECT PCM CIRCUIT FOR SHORT TO GROUND • Turn the ignition switch to the LOCK position. • Inspect for continuity between PCM terminal 1BH (Z6)/1C (LF) (wiring harness-side) and body ground. • Is there continuity?	Yes	Repair or replace the wiring harness, then go to Step 11.
10		No	Go to the next step.
11	VERIFY TROUBLESHOOTING OF DTC P0758 SHIFT SOLENOID B COMPLETED • Make sure to reconnect all the disconnected connectors. • Clear the DTC from the memory using the WDS or equivalent. • Drive the vehicle in D range and make sure that the gears shift smoothly from 1GR to 4GR. • Are any DTCs present?	Yes	Replace the PCM, then go to the next step.
11		No	Go to the next step.
12	VERIFY AFTER REPAIR PROCEDURE • Perform the “After Repair Procedure”. • Are any DTCs present?	Yes	Go to the applicable DTC inspection.
12		No	DTC troubleshooting completed.