Timing Reference High Resolution Signal A Intermittent/Erratic Pulses
The PCM detects intermittent or erratic pulses from the Timing Reference High Resolution Signal A sensor, which is used to determine precise engine timing and crankshaft position. This causes the engine control module to lose accurate timing reference data, affecting fuel injection and ignition timing.
What You Might Notice
- Check Engine Light illuminated
- Engine running rough or misfiring
- Hesitation or stumbling during acceleration
- Poor fuel economy
- Difficulty starting the engine
Most Common Causes
- 1
Faulty crankshaft or camshaft position sensor
The timing reference sensor may be failing and producing an intermittent or weak signal. Sensor degradation is the most common cause of this code.
- 2
Wiring damage or corroded connectors
Loose, corroded, or damaged wiring in the sensor circuit can cause signal interruptions. Check the sensor harness and connector pins for oxidation or poor contact.
- 3
Reluctor wheel damage or air gap issue
The reluctor ring on the crankshaft or camshaft may be damaged, cracked, or have an excessive air gap from the sensor, preventing proper signal detection.
- 4
Contaminated or degraded engine oil
Metal particles or debris in the oil can accumulate on the reluctor wheel or sensor, disrupting the timing signal. Low or dirty oil may also affect sensor operation.
How to Diagnose It
- 1
Check Faulty crankshaft or camshaft position sensor — The timing reference sensor may be failing and producing an intermittent or weak signal. Sensor degradation is the most common cause of this code.
- 2
Check Wiring damage or corroded connectors — Loose, corroded, or damaged wiring in the sensor circuit can cause signal interruptions. Check the sensor harness and connector pins for oxidation or poor contact.
- 3
Check Reluctor wheel damage or air gap issue — The reluctor ring on the crankshaft or camshaft may be damaged, cracked, or have an excessive air gap from the sensor, preventing proper signal detection.
- 4
Check Contaminated or degraded engine oil — Metal particles or debris in the oil can accumulate on the reluctor wheel or sensor, disrupting the timing signal. Low or dirty oil may also affect sensor operation.
How to Fix It
- 1
Replace timing reference position sensor
Remove and replace the crankshaft or camshaft position sensor that is generating the erratic signal. Verify the correct sensor location and part number for your vehicle before replacement.
- 2
Inspect and repair sensor wiring and connectors
Check the sensor harness for damaged insulation, corrosion, or loose connections. Clean corroded connector pins with contact cleaner and ensure a secure connection. Repair or replace damaged wiring as needed.
- 3
Inspect reluctor wheel and adjust sensor air gap
Remove the sensor and visually inspect the reluctor ring for cracks or damage. Verify the air gap between sensor and reluctor wheel meets specification (typically 0.020-0.050 inches). Adjust mounting if gap is excessive.
- 4
Perform engine oil and filter change
Drain old oil, replace the oil filter, and refill with fresh oil to specification. Metal debris or contamination can interfere with sensor operation; clean oil helps restore proper signal integrity.
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