P078A OBD-II: Shift Timing Solenoid "B"

P078A Severity

Urgent

Should you fix P078A yourself?

Identifying an OBD code is just the start of a complete diagnostic routine. Most trouble codes are caused by a sensor reporting a value that is out of range. Just replacing a sensor may not fix underlying issues. Be sure to understand the code, the part or system in your car that the code refers to, and the risks of delaying professional repair.

Proper diagnosis will save you time and money on unnecessary repairs.

Urgent codes indicate immediate action is necessary. These are urgent and significant malfunctions that can cause severe damage to the vehicle or harm the driver and passengers.

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What causes OBD-II fault code P078A?

The Transmission Control Module (TCM) uses shift solenoids to control the hydraulic pressure in the transmission which is needed to apply the various clutch packs in the transmission that provide the different gear ratios needed to efficiently propel the vehicle down the roadways. When the TCM detects a shift solenoid is not performing as desired, it will set code P078A.

OBD II Fault Code

OBD II P078A

OBD-II Code Transmission may not shift properly is defined as a Shift Timing Solenoid "B"

Transmission may not shift properly Symptoms

Increased fuel consumption
Transmission may not shift properly

Common Problems That Trigger the P078A Code

Transmission Control Module (TCM) failure
Transmission fluid level is low
Transmission shift solenoid failure
Transmission valve body failure
Wiring issue

OBD Code Resources

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OBD II Fault Code

OBD II P078A

OBD-II Code Transmission may not shift properly is defined as a Shift Timing Solenoid "B"

Transmission may not shift properly Symptoms

Increased fuel consumption
Transmission may not shift properly

Common Problems That Trigger the P078A Code

Transmission Control Module (TCM) failure
Transmission fluid level is low
Transmission shift solenoid failure
Transmission valve body failure
Wiring issue

P078A OBD-II: Shift Timing Solenoid "B"

Should you fix P078A yourself?

What causes OBD-II fault code P078A?

Need a P078A diagnosis? Trust our experts.

OBD II Fault Code

Transmission may not shift properly Symptoms

Common Problems That Trigger the P078A Code

OBD Code Resources

Ask our experts about P078A.

Other OBD-II Codes

OBD II Fault Code

Transmission may not shift properly Symptoms

Common Problems That Trigger the P078A Code