P1778
Step Motor Function
P1778 is an OBD-II diagnostic trouble code meaning: Step Motor Function. Common causes: stepper motor fault, problems with wiring or connectors. Estimated repair cost: $33–167.
Symptoms
- Gear shifting problems
- Hard or abrupt shifts
- Delays when shifting gears
- Switching to emergency mode of the gearbox
- Check Engine Light Illuminates
Causes
- Stepper motor fault
- Problems with wiring or connectors
- Low or contaminated transmission fluid
- Mechanical problems in the gearbox
- Transmission control module (TCM) malfunction
How to Fix
- Check the level and condition of the transmission fluid
- Diagnose stepper motor electrical circuits
- Check connectors and wiring for damage
- Test the operation of the stepper motor
- If necessary, replace the stepper motor
Related codes
Error P1778 by Vehicle Brand
FAQ
What does the P1778 code mean?
P1778 is an OBD-II diagnostic trouble code that indicates: Step Motor Function
What causes a P1778 error code?
The most common causes of P1778 include: Stepper motor fault; Problems with wiring or connectors; Low or contaminated transmission fluid; Mechanical problems in the gearbox.
How do I fix a P1778 diagnostic trouble code?
To fix P1778: Check the level and condition of the transmission fluid. Diagnose stepper motor electrical circuits. Check connectors and wiring for damage. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P1778?
Limited driving only, diagnose soon
How much does it cost to fix P1778?
The estimated repair cost for P1778 is $33–167. Actual cost depends on your vehicle, location, and labor rates.
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