P0372 - Timing Reference High Resolution Signal 'A' Too Few Pulses

Repair Importance Level: 3/3
Repair Difficulty Level: 2/3  What does this mean?

P0372 Possible Causes

  • Timing Reference Optical Sensor harness is open or shorted
  • Timing Reference Optical Sensor circuit poor electrical connection
  • Faulty Timing Reference Optical Sensor
  • Damaged Powertrain Control Module (PCM)

First diagnose P0372 code

    Check the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded terminals.

Cost of diagnosing the P0372 code

    Labor: 1.0

    The cost of diagnosing the P0372 code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.

When is the P0372 code detected?

Some high resolution pulses are missing from the optical sensor to the PCM

P0372 Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P0372 Meaning

The optical sensor provides a high resolution signal to the Powertrain Control Module (PCM) by counting pulses on the sensor disk located in the injection pump. The high resolution is one of the most important inputs by the PCM for fuel control and timing. This test monitors the number of high resolution pulses which have been missed (not detected). It's based on a comparison between the number of pulses that were detected since the last pump cam pulse and the number of the pulses that should have occurred. There are approximately 64 high resolution pulses for every cam pulse.
OBDII Code P0372 - Timing Reference High Resolution Signal 'A' Too Few Pulses - Engine-Codes.com

P0372 More Information

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