P1219: CID Stuck Low - Cylinder Identification Sensor Signal Low
The P1219 code indicates that the Engine Control Module (ECM) has detected the Cylinder Identification (CID) sensor signal is stuck low. The CID sensor, typically a Hall-effect sensor, provides the ECM with cylinder position information for proper fuel injection and ignition timing. A stuck low signal means the sensor output remains at a low voltage (near ground) when it should be pulsing. This can be caused by a faulty sensor, wiring issues (short to ground, open circuit), or a damaged reluctor ring. The ECM may disable fuel injection to the affected cylinder, leading to misfires and reduced engine performance.
01. Most Common Causes
- Faulty CID sensor
- Short to ground in CID sensor circuit
- Open circuit in CID sensor wiring
- Damaged reluctor ring or tone wheel
- Corroded or loose connector at CID sensor
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Reduced engine power and acceleration
- Hard starting or no start condition
- Poor fuel economy
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data. Verify P1219 is present.
Step 2: Visually inspect CID sensor and wiring for damage, corrosion, or loose connections.
Step 3: Test CID sensor signal with a multimeter or oscilloscope. Expected: 0-5V square wave when engine is cranking.
Step 4: Check for short to ground or open circuit in sensor wiring between sensor and ECM.
Step 5: Inspect reluctor ring for damage or debris. Replace if necessary.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended. Driving with a stuck low CID sensor can cause misfires, reduced power, and potential damage to the catalytic converter due to unburned fuel.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the cause. A new CID sensor costs around $20-$50, and labor is about $30-$100.