P0803 Code Meaning and Next Steps

First checks take 10 to 20 minutes for the first checks. No special tools are usually needed for the first checks.

Can you keep driving?

Stop driving if any of these apply

!The transmission slips, bangs into gear, or will not shift correctly.
!The vehicle loses drive, enters limp mode, or the warning light is paired with obvious transmission trouble.

If the light is steady and the vehicle still drives normally: Maybe, but only for a short distance if the transmission still shifts normally.

What to check first

Step-by-step checks

1
Free - no tools
Check the transmission connector and harness for damage, looseness, or fluid intrusion
2
Free - no tools
Notice whether the vehicle feels like it is shifting normally otherwise or whether it is stuck in a fallback pattern
3
Basic tool needed
Check for related transmission codes before replacing parts
4
Basic tool needed
If scan data is available, compare the commanded shift strategy with actual vehicle behavior
5
Basic tool needed
If the vehicle was recently serviced, verify the connector seating and fluid level first

If the code returns

-If wiring and fluid are normal, module testing or deeper valve-body diagnostics becomes more useful.
-If the code returns after a repair, confirm the controller still sees the fault before clearing it again.
-If the transmission behaves normally but the code returns, scan-data comparison becomes more useful than another visual check.

Background

What this code means

P0803 is a generic OBD-II code for the 1-4 upshift or skip-shift solenoid control circuit.

This is often more noticeable on vehicles that use a dedicated skip-shift or shift-control strategy, so the fault is usually electrical, control-side, or shared with another transmission code.

Treat it as a circuit diagnosis first and a component replacement second.

Diagnosis

Common causes

Most common

Shift-control solenoid fault

The solenoid may not open or close as commanded.

Common

Connector or harness issue

Loose connectors, damage, or corrosion can interrupt the circuit.

Common

Valve-body hydraulic issue

Hydraulic leakage or sticking can mimic an electrical fault.

Possible

Transmission control issue

The control module may not be able to command the solenoid correctly.

Avoid these mistakes

What not to do

xDo not keep driving if the transmission starts slipping or refuses to shift correctly.
xDo not assume the scan code identifies the exact failed part without checking the circuit and symptom pattern first.

Parts

Parts that may need replacing

PartTypical costNotes

Transmission fluid service$80-$250Useful if fluid condition or service history is suspect.

Shift-control solenoid or valve-body repair$150-$900Relevant when testing shows the control path is the problem.

Connector pigtail repair$20-$120Worth checking if the plug or pins are damaged.

Related OBD codes

P0700

P0700 usually means the transmission control system has a fault stored in the transmission module.

P0751

P0751 usually means shift solenoid A performance or stuck off.

P0785

P0785 usually means shift/timing solenoid malfunction.

Source notes

Generic OBD-II (SAE J1979 / ISO 15031-5). P0803 was seeded from dtcdb and then expanded around skip-shift solenoid control faults, including wiring, connector, and control-side issues.

This guide is written as a generic multi-make reference, so bulletin history, sensor locations, and repair order can still change by manufacturer and engine family.

This is generic OBD-II guidance and should not override vehicle-specific service information. Exact diagnosis and repair steps vary by make, engine family, and model year.

Last reviewed: 2026-04-10

Reference: Open reference

P0803 - P0803 Usually Means 1-4 Upshift (skip Shift) Solenoid Control Circuit Malfunction