P0803 Code: Meaning, Symptoms, Causes & Fix

P0803

Overview

When P0803 appears, the control module has detected abnormal behavior related to 1-4 Upshift (Skip Shift) Solenoid Control Circuit Malfunction in transmission and shift management.

Symptoms

  • harsh or delayed shifting
  • reduced acceleration
  • gear hunting

Common causes

  • Open circuit in wiring affecting 1-4 upshift (skip shift) solenoid control circuit malfunction
  • Broken terminal inside harness
  • Connector pin damage/corrosion or harness stress near related components

How to diagnose P0803

  1. Confirm P0803 and capture freeze-frame data with a professional scan tool.
  2. Inspect wiring, connectors, and grounds related to 1-4 upshift (skip shift) solenoid control circuit malfunction for obvious defects.
  3. Use a continuity test from module pin to component to identify opens/high resistance.
  4. Check for related DTCs to identify the root-cause chain before replacing parts.
  5. After repair, clear codes and confirm readiness monitors complete without recurrence.

Severity of code P0803

Moderate: This code is moderate severity: the vehicle may still operate, but fault progression can increase repair cost over time.

Can you drive with P0803?

Most vehicles can be driven short-term with P0803, but postpone heavy load/highway driving until repaired.

If the warning lamp is flashing or drivability/safety is affected, avoid driving and diagnose immediately.

How to fix it (step-by-step)

  1. Repair obvious wiring/connector faults first to prevent repeat parts replacement.
  2. Address the root fault mode (open) in the 1-4 upshift (skip shift) solenoid control circuit malfunction circuit/system.
  3. Apply the required relearn/adaptation procedure if specified by service information.
  4. Road-test and verify P0803 remains cleared under the conditions that originally set the code.

Fix options

  • Clear corrosion and protect terminals.
  • Restore continuity and verify pin tension.
  • Clear DTCs and verify with live data and completed drive cycle.

Typical repair cost

$300-$1500

Common mistakes when diagnosing P0803

  • Replacing parts without verifying voltage, ground, and signal integrity first.
  • Ignoring related stored/pending codes that indicate upstream faults.
  • Skipping post-repair verification drive cycle and readiness checks.

P0803 in common vehicles

P0803 appears across makes such as Nissan, Hyundai, Kia, Volkswagen. Failure patterns differ by platform: wiring routes, software calibration, and component supplier revisions can change root cause.

Frequently asked questions

What causes P0803?

P0803 is commonly set by open faults affecting 1-4 upshift (skip shift) solenoid control circuit malfunction.

How much does it cost to fix P0803?

For P0803, repair costs are typically $300-$1500 depending on exact root cause, labor rates, and part quality.

Can I clear P0803 without repair?

You can clear P0803 temporarily, but the code usually returns until the underlying fault is corrected.

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