P0372
Timing Reference High Resolution Signal A Too Few Pulses
When a vehicle powertrain module registers the fault code P0372, it points directly to an internal system malfunction identified as "Timing Reference High Resolution Signal A Too Few Pulses". Operating your engine under this condition may degrade long-term fuel maps.
Driver's Summary
Your vehicle's computer logged P0372 after detecting a malfunction in the timing reference high resolution signal a too few pulses system. In practice, this fault causes engine misses, dies, or won't start. This is not a code to ignore — the underlying fault can rapidly worsen and lead to costly repairs if driving continues.
Symptoms
Engine misses, dies, or won't start
Common Causes
- Broken teeth on optical disc or reluctor wheel
- Failing high resolution sensor
- Open circuit in signal wire
- Loose sensor mounting
How to Fix
- 1 Inspect and replace optical disc
- 2 Replace high resolution sensor
- 3 Repair broken signal wire
- 4 Tighten sensor hardware
Technical Explanation
The ECM detects code P0372 by continuously monitoring the relevant sensor circuit against calibrated threshold values stored in its non-volatile memory. The PCM monitors crankshaft rotational velocity via the CKP sensor at a resolution of individual tooth gaps on the reluctor ring. A combustion event in each cylinder produces a measurable acceleration spike; its absence or weakness is flagged as a misfire event within a 200-revolution or 1000-revolution test window. The fault remains stored in memory even after the MIL is cleared; it becomes a confirmed DTC after failing two consecutive drive cycles, and the PCM logs a freeze frame record of the engine's exact operating state at the moment of detection.
Is It Safe to Drive?
This fault carries real mechanical risk. The root causes — including broken teeth on optical disc or reluctor wheel — can trigger a chain reaction of component failures if the vehicle continues to be driven. Have it towed or drive directly to a shop without delay.
Mechanic's Pro Tip
The most common mistake with P0372 is replacing the sensor without verifying the reference voltage and ground integrity first. Use a scan tool to monitor the sensor's live output; a truly failed sensor shows a stuck, flatlined reading — a sensor that fluctuates but reads slightly off usually indicates a wiring or vacuum issue, not a dead sensor. Always spray electrical contact cleaner on the connector pins before condemning the sensor.
Related Fault Codes
Frequently Asked Questions
What does OBD2 code P0372 mean?
OBD2 code P0372 refers to Timing Reference High Resolution Signal A Too Few Pulses. When a vehicle powertrain module registers the fault code P0372, it points directly to an internal system malfunction identified as "Timing Reference High Resolution Signal A Too Few Pulses". Operating your engine under this condition may degrade long-term fuel maps.
What are the most common symptoms of DTC P0372?
Drivers experiencing code P0372 typically report: Engine misses, dies, or won't start.
Is it safe to drive with trouble code P0372 active?
This fault carries real mechanical risk. The root causes — including broken teeth on optical disc or reluctor wheel — can trigger a chain reaction of component failures if the vehicle continues to be driven. Have it towed or drive directly to a shop without delay.
How much does it cost to fix code P0372?
The estimated repair cost for P0372 ranges from $100 to $600 USD. Sensor replacement: 150 - 400
Sensor replacement: 150 - 400
Need Professional Diagnostic Assistance?
Always verify sensor signals and wiring integrity with an OBD2 scanner before purchasing replacement parts.
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