The P0370: Timing Reference High Resolution Signal A Malfunction code indicates that the engine control module (ECM) has detected an issue with the timing reference high-resolution signal A. This signal is critical for accurate engine timing and synchronization. A malfunction in this signal can be caused by sensor issues, wiring problems, or circuit failures.
P0370 – Quick Overview
Meaning | P0370: Timing Reference High Resolution Signal A Malfunction |
Is it serious? | Yes, this code can lead to inaccurate engine timing, causing misfires, rough idling, or stalling, which can lead to engine damage if unresolved. |
Possible causes | – Faulty timing reference signal – Signal disruption – Sensor or circuit issues |
How to diagnose? | – Test timing reference signal A – Inspect sensor and circuit – Repair or replace components if needed |
P0370 Meaning
The P0370: Timing Reference High Resolution Signal A Malfunction code means that the ECM is detecting an issue with the high-resolution timing reference signal A. This signal helps the ECM calculate precise timing for engine functions such as ignition and fuel injection. If the signal is disrupted, it can lead to poor engine performance, including misfires, stalling, or reduced power.
Step-by-step diagnostic guide
Follow these steps to diagnose and resolve the P0370 code by addressing potential causes one by one.
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check for additional related codes that may provide more information about the issue. | OBD-II Scanner |
Inspect the Timing Reference Sensor | Visually inspect the sensor for signs of wear, corrosion, or damage. Ensure it is properly mounted and securely connected. | Flashlight, Safety Gloves |
Test Timing Reference Signal A | Use a multimeter to measure the signal output from the timing reference sensor A. Compare the readings with the manufacturer’s specifications to ensure proper operation. | Multimeter, Manufacturer’s Specifications |
Inspect Circuit and Wiring | Inspect the wiring and connectors leading to the timing reference sensor A for any signs of damage, loose connections, or corrosion. Repair or replace as necessary. | Flashlight, Wiring Repair Kit |
Replace the Sensor if Necessary | If the sensor is faulty or providing incorrect signals, replace it with a new one to restore accurate timing. | Replacement Timing Reference Sensor, Safety Gloves |
Clear the Code and Test Drive | After completing repairs, clear the P0370 code using an OBD-II scanner. Test drive the vehicle to ensure the problem is resolved. | OBD-II Scanner, Vehicle Owner’s Manual |
Recheck for Codes | After the test drive, re-scan the vehicle to ensure the P0370 code has not returned. If the code reappears, further diagnosis may be required. | OBD-II Scanner |
This diagnostic guide will help you diagnose and fix the P0370 code, ensuring that timing reference signal A operates correctly, allowing the ECM to manage engine timing and synchronization properly.

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