Code
P1219
FORD
P — Powertrain
CID Low
AI status
Completed
Completed
100%
Causes
- Damaged or corroded CID sensor connector or wiring (open, short to ground, short to voltage)
- Failed CID sensor (camshaft position/CID sensor or injector feedback device)
- Poor or missing ground or battery supply to the sensor or PCM
- Incorrect cam/crank timing or timing chain/belt/slippage
- PCM internal fault or software issue
- Intermittent wiring due to heat, vibration, or water intrusion
Symptoms
- Malfunction Indicator Lamp (MIL) ON
- Rough idle, misfire or cylinder-specific misfire codes
- Hard starting or no-start condition
- Reduced power or limp-in mode
- Poor fuel economy and drivability issues
- Intermittent stalling
What to check
- Read stored and pending codes and capture freeze-frame data with a scan tool
- Check battery voltage and charging system (low supply can affect sensors)
- Visual inspection of CID sensor, connector, and wiring for corrosion, damage, or pin push-out
- Backprobe the CID signal connector and measure voltage while cranking and running
- Wiggle test harness while monitoring CID signal to reproduce fault
- Inspect cam/crank timing (timing marks, chain/belt tension) if available
Signal parameters
- Expected waveform: pulsed/square or digital switching waveform synchronized to cam/engine speed
- Typical amplitude: 0–5 V digital signal (CID considered 'low' when below ~0.5–1.0 V depending on model)
- Signal frequency: varies with engine RPM (higher frequency at higher RPM)
- Reference: sensor ground and 5 V or switched supply depending on sensor type
- A bad or open sensor may show stuck low (~0 V) or no waveform; a short to ground will hold signal low
Diagnostic algorithm
- Connect a scan tool, confirm P1219 and note freeze-frame data (engine speed, temperature, battery). Clear codes and attempt to re-run to confirm repeatability.
- Verify battery voltage >12.4 V with engine off and >13.5 V while running; weak supply can affect sensor outputs.
- Visually inspect CID sensor and connector for contamination, bent pins, or corrosion. Repair or clean as needed.
- Backprobe the CID signal, sensor power, and ground circuits. Compare voltages to expected values while cranking and running.
- Wiggle the wiring harness and connectors while monitoring signal to find intermittent faults.
- If signal is absent or held low, isolate wiring by disconnecting the sensor and measuring resistance to ground/power per service manual. Repair wiring faults before replacing parts.
- Use an oscilloscope to verify correct waveform and cam/crank correlation. If waveform is incorrect but wiring is good, replace the sensor.
- Inspect timing components if waveform phase is incorrect or cam/crank correlation faults are suspected.
- If wiring and sensor check good, check PCM power/ground and perform PCM reflash or replacement only after other causes are eliminated.
- After repairs, clear codes and perform a drive cycle to verify the fault does not return.
Likely causes
- Corroded/loose connector at the CID sensor or wiring harness
- Broken wire or chafed insulation causing a short to ground
- Failed CID sensor (open or shorted element)
- Weak battery/poor sensor supply voltage or ground
- Cam timing jumped or sensor reluctor damaged
Fault status
Status
CID circuit low — Cylinder Identification signal below expected threshold. May set MIL and cause misfires, no-start or drivability issues.
Repair difficulty: Medium
Diagnostic time: 1.0-3.0 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email