The P0803 trouble code indicates a malfunction in the 1-4 upshift (skip shift) solenoid control circuit.
P0803 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction
Code symptoms P0803.
1. Check Engine Light (CEL) or Malfunction Indicator Lamp (MIL) illumination on the dashboard.
2. The transmission may not shift properly or may experience delays during upshifting.
3. Other transmission-related symptoms such as harsh shifting or slipping may occur.
Causes of the code P0803.
1. Faulty 1-4 upshift (skip shift) solenoid.
2. Wiring or connector issues in the solenoid control circuit.
3. Corrosion or poor connections in the circuit.
4. A defective transmission control module (TCM) or powertrain control module (PCM).
Code Solutions P0803.
1. Use an OBD-II scanner to retrieve freeze frame data and any other stored trouble codes. This information can provide insight into when and how the malfunction occurred.
2. Inspect the wiring and connectors in the 1-4 upshift solenoid control circuit for damage, corrosion, or loose connections. Repair or replace any damaged components as needed.
3. Test the solenoid itself for proper operation. This may involve applying battery voltage and ground to the solenoid terminals and listening for an audible click or feeling for a mechanical movement.
4. Test the solenoid control circuit for continuity and proper voltage using a multimeter. If the circuit is open or has voltage issues, further diagnosis is necessary to determine the cause.
5. If the wiring and connectors check out okay, test the TCM or PCM for proper operation. This may involve using a diagnostic scan tool to communicate with the module and retrieve any stored trouble codes or data.
6. Clear the trouble codes from the vehicle’s computer memory and test drive the vehicle to see if the code returns. If it does, further diagnosis or repairs may be required.