What it means
Same as P23E1 with the control line shorted to supply. EGR mixes inert exhaust into intake to lower combustion peak temperature — too little raises NOx, too much causes misfires and rough running.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
EGR valve C controls exhaust-gas recirculation through the C stage or loop, where fitted. The module sets this code when the valve C control signal is high, consistent with a short to the supply; this differs from a low signal or an open circuit.
Common causes
Most likely first.
- Control line shorted to supply
- Connector pins corroded - high contact resistance
- Supply wire pinched against B+ source
Symptoms
- Check engine light
- Possible rough idle, hesitation, or reduced power
- Increased emissions or failed emissions test
How to diagnose it
- Save freeze-frame data and check whether the high control condition occurs continuously or only under particular operating conditions.
- Inspect the valve C harness for a pinched wire touching a supply source, damaged insulation, or heat-related damage.
- Check the valve C connector for corrosion, damaged terminals, or a pushed-back pin that could affect the control signal.
- With the circuit isolated as directed by the manufacturer, test the valve C control wire for a short to supply.
- If the harness and connector pass, check the circuit and module output against the manufacturer's specification.
Common fixes
- Repair a pinched valve C control wire and route it away from the supply source.
- Repair damaged insulation where the control wire contacts a supply wire or terminal.
- Clean or replace damaged EGR valve C connector terminals.
- Repair or replace the control module if circuit checks confirm an internal fault.
Can I keep driving?
If the engine runs normally, limited driving may be possible, but avoid heavy loads if power drops or the engine hesitates. Continued EGR control problems can increase emissions and cause rough running.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.