Many selectors read tap-up and tap-down over one shared wire with voltage steps or a resistor network; P0826–P0828 cover this shared circuit, P0815/P0816 the single directions. P0826 is the general fault of the shared circuit. GM (6L80 in 2011, 2019, 2025, hybrids) sets it when the circuit shows an invalid voltage for at least 60 s with 8.6–32 V and 400–7500 rpm, without MIL. On Saab's 9-4X with the 6T70 a short to ground or an open sets P0826. Saab's 2003–04 9-3 Sentronic reports below 0.2 V or above 6.7 V for over 30 s under P0826 with a fault-type byte, lights 'Check gearbox' and locks the lever in P/N. Ram's 2025 heavy-duty trucks set it with P0827 and P085F and the MIL, fixed with transmission software. Manual shifting is then disabled.
Medium severity. Can I keep driving?Drive as little as possible and gently. If the transmission slips or stays in one gear, go slowly to a repair shop or call for a tow truck.
Symptoms
- Tap or manual shifting not working
- Transmission runs only in automatic mode
- Transmission warning; lever locked in P/N (Saab 9-3)
Most likely causes
- Wire or connector between selector and module open or shorted
- Selector assembly (Hall switch, resistor network, module) faulty
- Transmission module software (Ram)
- Clockspring or steering wheel wiring (paddles)
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
What each character of P0826 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 8: Transmission
- 26: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0826?
Drive as little as possible and gently. If the transmission slips or stays in one gear, go slowly to a repair shop or call for a tow truck.
What causes code P0826?
The most common causes are: wire or connector between selector and module open or shorted; selector assembly (Hall switch, resistor network, module) faulty; transmission module software (Ram).
Related codes
- P0827Up and Down Shift Switch Circuit Low
- P0828Up and Down Shift Switch Circuit High
- P0815Upshift Switch Circuit
- P0816Downshift Switch Circuit
- P0819Up and Down Shift Switch to Transmission Range Correlation
Sources
- gsi.ext.gm.com: 19OBDG03C Diagnostics
- gsi.ext.gm.com: 11OBDG07 TRANS Diagnostics
- saabwisonline.com: dtc p0815 p0816 or p0826
- saabwisonline.com: p0826 06
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.