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DTC P0778 [FS5A-EL]

id050221810500

DTC P0778 | Pressure control solenoid B malfunction (electrical)
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DETECTION CONDITION | • If TCM detects either of the following conditions, TCM determines that pressure control solenoid B circuit has a malfunction. - Pressure control solenoid B voltage stuck at B+ after engine start - Pressure control solenoid B voltage stuck at 0 V after engine start Diagnostic support note: • This is a continuous monitor (CCM). • The MIL illuminates if the TCM detects the above malfunction conditions during the first drive cycle. • The PENDING CODE is available if the TCM detects the above malfunction condition during the first drive cycle. • FREEZE FRAME DATA is available. • The AT warning light illuminates. • The DTC is stored in the TCM memory.
POSSIBLE CAUSE | • Pressure control solenoid B malfunction • Short to ground in wiring harness between transaxle connector (secondary) terminal A and TCM terminal 1D • Short to power supply in wiring harness between transaxle connector (secondary) terminal A and TCM terminal 1D • Open circuit in wiring harness between pressure control solenoid B terminal B and transaxle connector (secondary) terminal A • Open circuit in wiring harness between transaxle connector (secondary) terminal A and TCM terminal 1B • Open circuit in wiring harness between pressure control solenoid B terminal A and body ground • Damaged connector between pressure control solenoid B and TCM • TCM malfunction

Diagnostic procedure

STEP | INSPECTION | ACTION
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1 | VERIFY FREEZE FRAME DATA HAS BEEN RECORDED • Has the FREEZE FRAME DATA been recorded? | Yes | Go to the next step.
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.
No | Go to the next step.
3 | INSPECT TRANSAXLE CONNECTOR FOR POOR CONNECTION • Turn the ignition switch to the LOCK position. • Disconnect the transaxle connector (secondary. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal? | Yes | Go to the next step.
No | Repair or replace the connector and/or terminals, then go to Step 11.
4 | INSPECT RESISTANCE • Inspect the resistance between transaxle connector (secondary) terminal A (transaxle case side) and body ground. • Is the resistance within 1.0-4.2 ohms? (See Resistance Inspection (On-Vehicle Inspection).) | Yes | Go to Step 7.
No | Go to the next step.
5 | INSPECT PRESSURE CONTROL SOLENOID B CONNECTOR FOR POOR CONNECTION • Disconnect the pressure control solenoid B connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal? | Yes | Go to the next step.
No | Repair or replace the connector and/or terminals, then go to Step 11.
6 | INSPECT RESISTANCE • Inspect the resistance between pressure control solenoid B terminals A and B (part-side). • Is the resistance within 1.0-4.2 ohms? (See Resistance Inspection (Off-Vehicle Inspection).) | Yes | Replace the solenoid wiring harness, then go to Step 11.
No | Verify shift pressure control solenoid B installation. • If solenoid installed correctly, replace the solenoid, then go to Step 11. (See SOLENOID VALVE REMOVAL/INSTALLATION (SECONDARY CONTROL VALVE BODY) [FS5A-EL].)
7 | INSPECT TCM CONNECTOR FOR POOR CONNECTION • Disconnect the TCM connector. • Inspect for poor connection (such as damaged/pulled-out pins, corrosion). • Is the connection normal? | Yes | Go to the next step.
No | Repair or replace the connector and/or terminals, then go to Step 11.
8 | INSPECT TRANSAXLE CONNECTOR CIRCUIT FOR OPEN CIRCUIT • Inspect for continuity between TCM terminal 1D (wiring harness-side) and transaxle connector (secondary) terminal A (wiring harness-side). • Is there continuity between terminals? | Yes | Go to the next step.
No | Repair or replace the wiring harness, then go to Step 11.
9 | INSPECT TRANSAXLE CONNECTOR CIRCUIT FOR SHORT TO POWER SUPPLY • Turn the ignition switch to the ON position (engine off). • Inspect the voltage at transaxle connector (secondary) terminal A (wiring harness-side). • Is the voltage 0 V? | Yes | Go to the next step.
No | Repair or replace the wiring harness, then go to Step 11.
10 | INSPECT TCM CIRCUIT FOR SHORT TO GROUND • Turn the ignition switch to the LOCK position. • Inspect for continuity between TCM terminal 1D (wiring harness-side) and body ground. • Is there continuity? | Yes | Repair or replace the wiring harness, then go to Step 11.
No | Go to the next step.
11 | VERIFY TROUBLESHOOTING OF DTC P0778 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 5GR. • Are any DTCs present? | Yes | Replace the TCM, then go to the next step. (See TCM REMOVAL/INSTALLATION [FS5A-EL].)
No | No concern is detected. Go to the next step.
12 | VERIFY AFTER REPAIR PROCEDURE • Perform the "After Repair Procedure". (See AFTER REPAIR PROCEDURE [FS5A-EL].) • Are any DTCs present? | Yes | Go to the applicable DTC inspection.
No | DTC troubleshooting completed.