P0342: Camshaft position sensor signal reads too low (circuit low input)

Camshaft position sensor circuit low input

Severity: Inspect soon

A weak or missing camshaft signal can cause hard starting, stalling or a no-start, and owners report lost power with backfiring, so book a check soon rather than keep driving on it.

Source: how we rate severity

P0342 in short

P0342 means the engine computer sees a camshaft position sensor signal that is too low, which usually points to a shorted sensor or wiring. Expect hard starting, rough running or stalling. A failed sensor or damaged connector is the most common cause. Get it checked soon, because the engine may not restart.

The camshaft position sensor tells the engine computer where the camshaft is, so it can time the fuel injectors and spark. If the signal from the sensor circuit stays lower than the computer expects, it stores P0342.

TroubleCodes.net describes the fault as low resistance, or a short, in the sensor circuit, and places this code on the bank 1 camshaft sensor A. The Delaware DMV list gives the same generic title: camshaft position sensor circuit low input.

The usual causes are the sensor itself, a damaged or wet connector, or wiring that has chafed or been chewed. Ford has also issued a PCM update for 2008 Super Duty trucks with the 6.4L diesel that covers intermittent P0342.

Most likely causes

Cause 1: Camshaft position sensor with an open or shorted coil
Common general cause
Why it ranks here
TroubleCodes.net lists a faulty sensor first, and the low-input code points at a short inside the sensor or its circuit. Owners also report the code with a camshaft sensor diagnosis.
What would change this
Rises if the sensor reads open or shorted on a resistance check, or the cranking signal is weak. Falls if the sensor tests normal and the wiring is damaged.
How to test the camshaft position sensor
Cause 2: Damaged, corroded or water-soaked wiring or connector
Common general cause
Why it ranks here
TroubleCodes.net lists wiring damage from repairs, impact or rodents, water in the connector, and brittle connectors as common causes of a short in this circuit.
What would change this
Rises if the connector shows corrosion or water, or wiggling the harness changes the reading. Falls if the harness and connector look clean and test fine.
Cause 3: Sensor loose, wrongly fitted or too far from the reluctor wheel
Possible — needs testing
Why it ranks here
TroubleCodes.net lists poor installation or wrong clearance to the reluctor ring. It is a smaller cause that mostly applies after the sensor has been removed or replaced.
What would change this
Rises if the code appeared after work near the sensor. Falls if the sensor sits fully seated with the right clearance.
Cause 4: Engine computer software that needs an update (2008 Ford 6.4L Super Duty)
Supported by vehicle data
Why it ranks here
Ford has a PCM update for 2008 F-450 to F-750 Super Duty trucks built before 30 July 2007 for intermittent P0342 and/or P1326. It applies to that one engine only, so it ranks below the general causes.
What would change this
Rises if a dealer says the VIN is covered and the PCM is not updated. Falls on any other vehicle, or if the update is already done.
How to test the engine control module (ecm / pcm)
Cause 5: Timing drive or crankshaft sensor problem
Possible — needs testing
Why it ranks here
TroubleCodes.net says to rule out a jumped timing belt or a crankshaft sensor problem. These are less likely behind a low-input code but can look the same.
What would change this
Rises if the crankshaft code (P0335) is also stored or the timing marks are off. Falls if no other cam or crank code is stored.
How to test the crankshaft position sensor

What to test first

Start at step 1. Each result tells you what it means and where to go next.

Step 1: Read all stored codes and the freeze-frame data with a scan tool, and note whether any crankshaft or other camshaft codes are stored with P0342.
Low riskTool: OBD-II scan tool
- IfOnly P0342 is stored
  It meansStart with the wiring and connector.
  Go to step 2
- IfA crankshaft code such as P0335 is stored too
  It meansThe timing drive or crankshaft sensor may be involved.
  Points to: Timing drive or crankshaft sensor problem
Step 2: With the engine off, look over the camshaft sensor connector and the visible harness for damage, corrosion, water or rodent chewing, and check the sensor is seated.
Low risk
- IfThe connector is corroded or wet, or the wire is chafed or chewed
  It meansA short in the wiring or connector is likely.
  Points to: Damaged, corroded or water-soaked wiring or connector
- IfThe sensor is loose or not fully seated
  It meansInstallation is a possible cause.
  Points to: Sensor loose, wrongly fitted or too far from the reluctor wheel
- IfEverything looks sound
  It meansTest the sensor itself.
  Go to step 3
Step 3: Have the sensor resistance checked for an open or short, and have the AC signal checked while the engine cranks. TroubleCodes.net says a healthy sensor shows at least about 20 mV AC while cranking.
Use cautionTool: multimeter
Warning:The engine is cranked during this test, so keep hands, hair and tools clear of belts and fans, and disable fuel or ignition as the shop does it.
- IfResistance reads open or shorted, or the cranking signal is missing or weak
  It meansThe sensor is the likely fault.
  Points to: Camshaft position sensor with an open or shorted coil
- IfThe sensor tests normal
  It meansTest the circuit between the sensor and the computer, and ask about an update.
  Go to step 4
Step 4: Ask a dealer whether your VIN has a PCM update for P0342. Ford has one for 2008 6.4L Super Duty trucks.
Low risk
- IfAn update applies and has not been done
  It meansDo the update before replacing parts.
  Points to: Engine computer software that needs an update (2008 Ford 6.4L Super Duty)
- IfNo update applies
  It meansHave the circuit between the sensor and the PCM tested for a short.
  Go to step 2

Symptoms

Engine cranks but is hard to start, or does not start
Engine stalls after starting or while driving Gets more serious: stop and have it checked.
Rough running or misfire
Weak acceleration
Check engine light on

How to fix

Step 1: With the engine off, look over the camshaft sensor connector and visible wiring for damage, corrosion or water.
Step 2: If you have a Ford 6.4L Super Duty, ask a dealer whether your PCM has the update for intermittent P0342.

Parts and cost context

Camshaft position sensor:Sensors are usually a modest part, but test the sensor and wiring first so you do not replace a good one. Labour varies by engine; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Ford

2008 · F-450 Super Duty
Supported by vehicle data
Ford bulletin 07910 updates the PCM on 2008 6.4L Super Duty trucks built before 30 July 2007 for intermittent P0342 and/or P1326. Whether it is still current is not verified.

07910Status unverified
6.4L PCM update for intermittent P0342 and/or P1326
2008f-450-super-duty · issued June 25, 2007 · NHTSA 10021904
Updates the PCM on 6.4L trucks built before 30 July 2007 for intermittent P0342 and/or P1326. The summary also lists PTO, turbo protection, high idle and shift quality changes.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

All Ignition and engine position sensors codes

P0342 questions

Will P0342 stop the car starting?

It can. Owners and TroubleCodes.net list hard starting, start-and-stall and no-start, depending on whether the computer can use another signal.

Do I replace the sensor straight away?

Test it and its wiring first. A damaged connector or wire gives the same code and a new sensor would not fix it.

Sources and review

TroubleCodes.net DTC pages (P0342, P0385, P0394, P0400, P0431, P0447; P0413, P0414, P0416, P0417 read but not used) — TroubleCodes.net
NHTSA complaint ODI 10641506: 2001 Newmar Mountain Aire — NHTSA Office of Defects Investigation (consumer complaint)
NHTSA complaint ODI 10140264: 2000 Daewoo Lanos — NHTSA Office of Defects Investigation (consumer complaint)
NHTSA complaint ODI 10262777: 2000 Daewoo Leganza — NHTSA Office of Defects Investigation (consumer complaint)
Ford 07910: 6.4L PCM update for intermittent P0342 and/or P1326 (2008 F-450 to F-750 Super Duty) — Ford / NHTSA , June 25, 2007
On-Board Diagnostic Trouble Codes (generic code title list) — Delaware Division of Motor Vehicles

Last reviewed: October 16, 2026
Written by: Saurabh K.
Editorial review: Pending
Technician review: Technician review pending

This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error

Severity: Inspect soon

Most likely causes

Cause 1: Camshaft position sensor with an open or shorted coil

Cause 2: Damaged, corroded or water-soaked wiring or connector

Cause 3: Sensor loose, wrongly fitted or too far from the reluctor wheel

Cause 4: Engine computer software that needs an update (2008 Ford 6.4L Super Duty)

Cause 5: Timing drive or crankshaft sensor problem

What to test first

Step 1: Read all stored codes and the freeze-frame data with a scan tool, and note whether any crankshaft or other camshaft codes are stored with P0342.

Step 2: With the engine off, look over the camshaft sensor connector and the visible harness for damage, corrosion, water or rodent chewing, and check the sensor is seated.

Step 3: Have the sensor resistance checked for an open or short, and have the AC signal checked while the engine cranks. TroubleCodes.net says a healthy sensor shows at least about 20 mV AC while cranking.

Step 4: Ask a dealer whether your VIN has a PCM update for P0342. Ford has one for 2008 6.4L Super Duty trucks.