The counterpart to P2648: the control circuit of rocker arm actuator A on bank 1 reads high, which means a short to battery voltage or a driver that cannot pull the line down. In GM's 2015 table 15OBDG05 the check needs the output driver commanded on, ignition in crank or run and supply above 11 V; 100 failures in 120 samples set a Type A fault. The Honda V6 (L66) in GM's 2004 table looks at the opposite situation: with the VTEC solenoid commanded off, a return signal at 12 V lasting 2 s points to a high circuit. A harness shorted to a power feed or an internal controller fault are the usual suspects; the actuator can then stay energised or be shut down by the controller.
Medium severity. Can I keep driving?If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
Bank 1 is the side of the engine with cylinder 1. Inline engines only have this bank.
Symptoms
- MIL on immediately
- Lift switching disabled or permanently active
- Rough running at idle if the actuator stays energised
Most likely causes
- Control wire shorted to a battery or ignition feed
- Output driver in the engine controller no longer switches
- Open ground side of the solenoid circuit
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: medium
- It can trigger limp mode.
- It affects emissions.
What each character of P2649 means
- P: Powertrain: engine and transmission
- 2: Generic code: same on every make
- 6: Control modules and outputs
- 49: Specific fault in that system
Frequently asked questions
Can I keep driving with code P2649?
If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
What causes code P2649?
The most common causes are: control wire shorted to a battery or ignition feed; output driver in the engine controller no longer switches; open ground side of the solenoid circuit.
Related codes
- P2645"A" Rocker Arm Actuator Control Circuit/Open (Bank 1)
- P2648"A" Rocker Arm Actuator Control Circuit Low (Bank 1)
- P2659"A" Rocker Arm Actuator Control Circuit High (Bank 2)
- P2654"B" Rocker Arm Actuator Control Circuit High (Bank 1)
Sources
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.