Powertrain, generic · Ignition system or misfire

P0343 Camshaft Position Sensor A Circuit High Bank 1 or Single Sensor

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

P0343 means the signal of the intake camshaft sensor of bank 1 (or the only cam sensor) stays at supply level without edges. Causes are a signal wire shorted to positive, an open signal wire that the module's pull-up holds at 5 V, a broken sensor ground or a faulty sensor. Ford's 2023 diesel sets it when the signal stays at system voltage over 10 or more crank revolutions (3 s). On the Saab 9-4X V6 (GM LAU) the signal must stay high without pulses for more than 1 s, or 10 s cumulatively, and the code follows after two trips. Saab's Motronic 2.8.1 (900 V6) treats low and high together and allows an air gap of at most 1.5 mm. The consequences are as for P0340: longer cranking, cam timing switched off, loss of power.

Likely causes

Signal wire open or shorted to positive
Sensor ground open
Camshaft position sensor faulty
Connector corroded

Symptoms

  • Check engine light on
  • Longer cranking before the engine starts
  • Loss of power (cam timing held in its base position)
  • Rough idle, occasionally stalling

Repair estimate

DifficultyEasyDIY possible
Parts and labour€30–300
Time0.3–2 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

camshaft position sensorcamshaft tone wheelsensor wiringengine control module

Related codes

P0340P0342P0348P0368

References: fordservicecontent.com, saabwisonline.com, saabwisonline.com, law.cornell.edu.