P1122

What does P1122 mean?

P-code P1122 means "Engine Coolant Sensor intermittent/ECT Sensor Intermittent". It is a manufacturer-specific diagnostic trouble code (DTC) in the HVAC / climate control. The engine coolant sensor intermittent/ect sensor intermittent signal is absent or intermittent, preventing the control module from monitoring this parameter. This code can be monitored, but service is recommended to prevent escalation. This code applies to OBD-II compliant electric and hybrid vehicles.

Possible Causes

• Sensor has completely failed and produces no output signal
• Disconnected or severely corroded electrical connector
• Broken wire in the signal path between sensor and module
• Control module failure unable to process the incoming signal

Recommended Actions

1. 1 Note the alert and schedule a diagnostic appointment when convenient
2. 2 Scan for all DTCs with an OBD-II scanner — note any related codes stored alongside P1122
3. 3 Inspect the HVAC / climate control component and its wiring for visible damage
4. 4 Check for water intrusion in connector areas and clean contacts if corroded
5. 5 Clear the DTC, road-test the vehicle, and re-scan to confirm whether the fault returns
6. 6 If the fault persists after inspection and clearing, consult an EV-certified technician for component replacement

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