P0829 - 5-6 Shift Malfunction
The P0829 code indicates a problem with the 5-6 shift in automatic transmissions, typically found in vehicles with 6-speed transmissions. This code is set when the powertrain control module (PCM) detects a malfunction during the shift from 5th to 6th gear, such as incorrect gear ratio, slippage, or mechanical failure. Common causes include low transmission fluid, faulty shift solenoids, valve body issues, or internal transmission damage.
01. Most Common Causes
- Low or contaminated transmission fluid
- Faulty shift solenoid (e.g., solenoid 'E')
- Worn or damaged valve body
- Internal transmission mechanical failure (e.g., clutches, bands)
02. Symptoms You Will Notice
- Harsh or delayed shifting
- Transmission slipping out of gear
- Check Engine Light illuminated
- Reduced fuel economy
03. Step-by-Step Diagnosis
Step 1: Check transmission fluid level and condition; top off or replace if necessary.
Step 2: Scan for additional codes and perform a transmission pressure test.
Step 3: Inspect wiring and connectors to the shift solenoids for damage or corrosion.
Step 4: Test shift solenoid resistance and operation; replace if faulty.
Step 5: If solenoid is OK, inspect valve body for wear or debris; rebuild or replace as needed.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive with this code as it can lead to further transmission damage and unsafe driving conditions. Have the vehicle inspected immediately.
How much does it cost to fix?▼
The cost varies depending on the cause. A simple fluid change may cost $50-$150, while solenoid replacement can range from $200-$500. Major transmission repairs can exceed $1,500.