What it means
The ECM detects a circuit high fault on the battery charger coupler temperature sensor d circuit. Reading cannot be used reliably for control.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Temperature sensor D monitors a specific area of the battery-charger coupler. P2E52 sets when the control module detects a D circuit signal above its expected electrical range, which can result from a signal short to battery voltage or an open sensor circuit and may cause charging limits.
Common causes
Most likely first.
- Signal wire shorted to B+
- Open sensor
- Connector pins corroded - high contact resistance
Symptoms
- Charge status indicator shows fault
- Charging may not start or interrupts
- Slower-than-expected charge rate
How to diagnose it
- Check freeze-frame data and live readings for sensor D, noting whether its signal is high while the other coupler temperature readings remain plausible.
- With charging safely stopped, inspect the D sensor connector and harness for disconnection, corrosion, moisture, or damaged insulation.
- Check the sensor D signal wire for a short to battery voltage using the manufacturer's wiring information.
- Test for an open in the sensor D circuit and test the sensor itself according to the manufacturer's procedure.
- Repair the confirmed fault, then verify a plausible D reading and normal charging operation.
Common fixes
- Reconnect a disconnected sensor D plug or repair a loose terminal.
- Repair a D signal wire shorted to battery voltage or an open in the circuit.
- Clean or replace damaged sensor D connector terminals.
- Replace temperature sensor D if it is open or fails the specified test.
Can I keep driving?
Charging may be limited or interrupted because the control module cannot trust sensor D's temperature reading. Stop charging if the coupler becomes unusually hot or the connector is damaged.
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.