What does it mean?
P1253 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: VTEC Solenoid Circuit Malfunction .
Symptoms
- The MIL is on and the high lift profile is disabled
- The engine feels flat above mid range, with no pull at higher rpm
- Reduced power and slower acceleration than normal
- Slightly higher fuel consumption in mixed driving
- The engine runs normally at idle and low load, so the fault is easy to miss around town
Likely causes
- Open or shorted winding inside the solenoid
- Control wire chafed against the cylinder head or a bracket and shorted to ground
- Oil contamination or corrosion inside the solenoid connector
- Loose, backed-out or corroded terminals at the solenoid or in an inline connector
- Broken wire in the section of loom that flexes with engine movement
- Poor ground or low supply voltage on the solenoid circuit
- Module driver failure, once the harness and solenoid are proven good
How to fix it
- Command the solenoid on with the scan tool while listening for the click and for a change in engine note at raised rpm
- Inspect the solenoid connector for oil, corrosion and terminal tension, and check the loom for rub marks against the head
- Unplug the solenoid and measure winding resistance against specification, plus insulation to ground
- Check for supply voltage and a clean ground at the connector with the circuit commanded on
- Test the control wire back to the module for continuity and shorts with both ends disconnected
- Check engine oil level and condition at the same time, since sludge often accompanies solenoid faults
- Replace the solenoid and clean or renew its filter screen when the electrical tests confirm the fault, then verify operation on live data