Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. P0374 OBD-II Trouble Code: Timing Reference High Resolution Signal A No Pulses

P0374 OBD-II Trouble Code: Timing Reference High Resolution Signal A No Pulses

Check engine Light

What the P0374 code means

The Powertrain Control Module (PCM) has discovered a problem in the high-resolution timing reference signal.

What causes the P0374 code?

There may be one or more causes for the P0374 code:

  • A defective camshaft, crankshaft, and distributor position sensors

  • Mechanical distributor failure, which occurs often in rear-wheel drive vehicles with high-mileage

  • Damaged, corroded, or faulty wiring and electrical connectors

  • PCM failure is possible but this very rarely occurs

What are the symptoms of the P0374 code?

Some symptoms are detectable while others are not. For instance, you might experience engine misfire and spark knock while you are accelerating. You may also experience lower fuel mileage. Malfunction lamp illumination may require several failure cycles, depending on what model you have.

How does a mechanic diagnose the P0374 code?

A good starting point for performing a successful diagnosis of the crankshaft position sensor is to check for an engine RPM signal while the engine is running or cranked. This can be done using a scanner or simply by observing your vehicle’s tachometer as the engine is running or being cranked. If you do not see an RPM signal, then inspect the crankshaft position sensor, crankshaft gear, and sensor connector for damage. You will want to repair as soon as possible. If you do not see any signs of damage, you will want to test the CPS system for a reference voltage signal. If you cannot find a pattern, then test the resistance of the CPS sensor and compare those values with the manufacturer’s specifications. If the CPS sensor seems to be working well, then test the system circuitry for the proper resistance and voltage. Always be sure to repair open or shorted wiring as you go. But remember that several specialty tools will be required to diagnose this code successfully. These may include a digital volt/ohmmeter, a scanner, and possibly an oscilloscope.

Common mistakes when diagnosing the P0374 code

Some mistakes include:

  • Unnecessary replacement of camshaft, crankshaft, and distributor sensors.

  • Crank and cam reluctor rings also need to be checked any time you are replacing sensors.

  • When replacing crankshaft or camshaft sensors, you should do these as a set. You might also want to use of OEM sensors as well.

How serious is the P0374 code?

The P0374 code is very serious and should be repaired as soon as possible. Luckily, to repair this issue is not as difficult as some others. But you will want to make sure that as soon as you see this code, you either begin addressing your issue yourself or take your vehicle into a professional technician.

What repairs can fix the P0374 code?

If your optical sensor circuit is damaged, you will want to repair this immediately. You will do this by removing your optical sensor. In rare cases, you will need to replace your PCM or ECM.

Additional comments for consideration regarding the P0374 code

The optical sensor in your vehicle provides a high-resolution signal to the Powertrain Control Module (PCM) by counting pulses on the sensor disk, which is located in your vehicle’s injection pump. One of the most important by the PCM for fuel control and timing, the optical sensor monitors the number of high-resolution pulses which have gone undetected. While you might be able to perform the maintenance by yourself, you will need to be patient and do the proper research in advance. But remember that it is always important to have the right diagnostic tools so that you know just what problems you are searching for and if you have located the correct problem or not. Do not hesitate to consult a professional, even if it is only to ask questions about doing the work yourself. Also, remember to test drive the vehicle and note if the code appears again.

Need help with a P0374 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
How to Buy Fuel Treatments
Adding a fuel additive to your gas tank when you fill up is one way to clean vital engine parts of deposits, improve the performance of your engine,...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...


Related questions

Q: Code p0101

The P0101 trouble code may keep returning if the engine computer does not see the MAF sensor input within a specified range when it is testing the MAF input. The input can be wrong if the engine has another problem...

Q: Getting code P0135

Hello. A P0135 code indicates that there is a malfunction of the oxygen sensor/heat circuit. This problem could cause the car to burn more gas and over time, cause damage to the catalytic converter. When the oxygen sensor is replaced...

Q: Error code P0171 and P0374

Hi and thanks for contacting YourMechanic. If the vehicle went into limp mode, then the computer is making this happen to prevent the engine from any damage. Check the camshaft sensor for proper timing to the camshaft. Look at the...