P0376 — Timing Reference High Resolution Signal B Too Many Pulses

What does code P0376 specifically mean?

P0376 means the controller received more pulses than expected from Timing Reference High Resolution Signal B. The fault points to an unstable or false-edged timing signal rather than simply a general engine-performance problem.

Is P0376 always a camshaft-position-sensor code?

No. P0376 identifies a high-resolution timing-reference circuit, and the physical sensor may be associated with crankshaft or camshaft position sensing depending on the vehicle. Confirm the Signal B assignment with the wiring diagram.

What commonly creates too many pulses for P0376?

Typical P0376 causes include a cracked reluctor, a failing position sensor, incorrect sensor spacing, contaminated or damaged wiring, and connector noise. A scope check is important because a pulse counter alone may not reveal the defect.

Can the vehicle be driven with P0376?

Driving may be possible if the signal remains stable, but stalling or sudden power loss is possible. Avoid extended or high-load driving and arrange diagnosis promptly, especially if the engine cranks but does not start normally.

Pulling code P0376 from your OBD2 scanner tells you the engine computer has detected an irregularity in the high-resolution timing reference signal circuit, specifically noting too many pulses were received. This falls under the powertrain category in the OBD2 system, which covers everything from engine operation to transmission functions. The powertrain control module continuously tracks this signal while the engine runs, watching for anything that falls outside the expected parameters.

When the signal stays out of spec for too many consecutive drive cycles, the module stores P0376 and activates the Check Engine light. The freeze frame data saved alongside this code is particularly useful — it records engine RPM, load, temperature, and vehicle speed at the exact moment the fault occurred. That snapshot gives you a solid starting point for tracking down what went wrong.

The high-resolution timing reference signal feeds critical engine management functions, including precise control of fuel injection events and ignition timing. Modern engines rely on this signal heavily, especially those with direct injection or variable valve timing systems. When the control module sees more pulses than it expects from this circuit, it sets P0376 because accurate timing synchronization becomes uncertain.

Common Symptoms of P0376

The Check Engine light will be illuminated once this code sets. The system or component tied to this timing reference typically operates intermittently or fails completely. Some vehicles enter limp mode depending on which sensor or actuator is affected, restricting performance to protect the engine. Increased fuel consumption occurs in certain cases because the engine management system falls back to less efficient operating strategies. Acceleration may feel sluggish or hesitant during the fault window. In rare scenarios, the engine may stumble or misfire slightly as timing signals become unreliable.

What Causes P0376

Corroded, loose, or damaged connectors at the sensor or control module create intermittent electrical contact, causing signal fluctuations the module interprets as excess pulses. Poor ground connections at the affected component starve the circuit of a solid reference voltage, leading to noisy or erratic signals. Damaged wiring in the harness — whether from chafing against engine components, heat damage, or rodent bites — introduces additional pulses or signal dropout. A blown fuse protecting the circuit cuts power entirely, leaving the module without a valid timing reference signal. A faulty sensor or actuator in the circuit sends incorrect data back to the control module, triggering the too-many-pulses flag. The control module itself may have an internal driver failure, though this ranks as the least common cause.

How to Diagnose P0376

Connect your OBD2 scanner and confirm P0376 is stored, then record the freeze frame data immediately — this data shows exactly what the engine was doing when the fault triggered and guides your inspection. Pull any related trouble codes as well, since secondary codes often point directly to the failing component. Check for manufacturer technical service bulletins for your specific make and model; some P0xxx codes have known factory fixes or require software updates the dealer can perform. Visually inspect all wiring and connectors associated with the timing reference circuit, looking for broken insulation, green corrosion buildup, bent pins, or loose plugs that could interrupt the signal. Use a multimeter to verify proper reference voltage, ground continuity, and signal integrity at the component connector before declaring a part faulty. Perform a wiggle test on the harness while monitoring live data on your scanner — any signal dropout or fluctuation during movement reveals broken wires hidden inside the insulation. Once repairs are complete, clear the code and drive the vehicle through a complete drive cycle that reproduces the conditions from the freeze frame data, then re-scan to confirm P0376 does not return.

Repair Options and Costs

Wiring harness repair or connector replacement typically runs $80 to $250, addressing corroded pins, broken wires, or loose plugs — the most common source of this fault. Replacing a faulty sensor or actuator in the circuit generally costs $150 to $500 for parts and labor, depending on which component your specific vehicle uses. Control module diagnosis and repair, if needed, ranges from $300 to $1,000, though this is rarely the first component to suspect.

Total Repair Cost for P0376

The total bill depends entirely on what component is actually at fault. Most P0376 repairs fall between $80 and $250 when the issue is wiring or connectors. Sensor or actuator replacement brings the total to $150 to $500. Control module work represents the high end at $300 to $1,000. The key is performing a proper diagnosis before purchasing parts — the most expensive scenario is almost never where you should start, and skipping the cheaper possibilities first means wasted money on unnecessary parts.

Can You Drive with P0376?

In most cases, your vehicle remains drivable with P0376 stored, though you may notice reduced performance or an auxiliary system operating in fail-safe mode. If the car stalls unexpectedly, refuses to start, or displays warnings related to braking or steering assist, treat this as a serious situation and discontinue driving until the fault is diagnosed and repaired.

Related OBD2 Codes

• P0300: Random/Multiple Cylinder Misfire Detected
• P0301: Cylinder 1 Misfire Detected
• P0302: Cylinder 2 Misfire Detected
• P0303: Cylinder 3 Misfire Detected
• P0304: Cylinder 4 Misfire Detected
• P0305: Cylinder 5 Misfire Detected