DTC Advanced Diagnostics: P034B (3.0L Engine)
DTC P034B: Crankshaft Position (CKP) Sensor Direction Incorrect
General Description
The crankshaft position (CKP) sensor consists of a rotor and a semiconductor that detects rotor position. When the engine starts, the rotor turns and the magnetic flux in the semiconductor device changes. The changes of magnetic flux are converted into pulsing signals to the powertrain control module (PCM). The CKP sensor detects injection/ignition timing for each cylinder and engine speed. At the timing of starter on, the PCM determines a backward of the crankshaft. If the PCM detects a backward rotation of the crankshaft during the ON of the starter, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | 100 milliseconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | |
|---|---|
| Starter | On |
Malfunction Threshold
The PCM detects a backward rotation of the crankshaft during the ON of the starter.
Possible Cause
- CKP sensor failure
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.