Yale 522752-2 – ECM or DEPR: Crank Loss (CAM Pulse without Crank Pulse)

This fault code indicates a loss of synchronization data between the engine's position sensors. Specifically, the controller is receiving a pulse signal from the Camshaft Position Sensor, but it is missing the expected corresponding pulse signal from the Crankshaft Position Sensor.

• Yale and Hyster Forklifts
• VX series
• GDP20VX
• GDP35VX
• GLC030VX
• GLP050VX
• GLC060VX
• Hyster FT series

1. 1

   Check the Crankshaft Position Sensor housing for dust, dirt, or debris that could be blocking the magnetic/Hall-effect signal.

2. 2

   Verify that the timing belt is tensioned properly. A loose, jumped, or broken timing belt will cause the cam and crank to lose synchronization, triggering this code and resulting in a no spark condition.

3. 3

   Inspect the wiring and connections at the Crankshaft Position Sensor for loose, damaged, or corroded terminals. Check for an open circuit on the sensor ground or supply circuits, as well as open or shorted signal wires.

4. 4

   Check related engine management relays and fuses to ensure the sensor circuit is receiving power.

5. 5

   If applicable to DEPR systems: With the key ON, measure the CAN HI and CAN LO voltages at the sensor connectors (should be approximately 2.5 Vdc). Measure the resistance across the CAN pins (should be 60 ± 6 ohms). If resistance is 120 ohms, there is an open circuit; if 0 ohms, the circuits are shorted.

1. 1

   Clean sensor housing

   Clean any dust or debris from the Crankshaft Position Sensor and its housing.

2. 2

   Re-tension or replace timing belt

   If the timing belt is found to be loose or damaged during diagnostics, re-tension or replace the timing belt to restore mechanical synchronization.

3. 3

   Repair wiring or connectors

   Repair or replace any damaged wiring harnesses or connectors leading to the Crankshaft Position Sensor.

4. 4

   Replace Crankshaft Position Sensor

   If the wiring, power supply, and timing belt are all in good condition, the Crankshaft Position Sensor has failed. Remove the mounting bolt, pull the old sensor, and install a replacement Crankshaft Position Sensor.

5. 5

   Replace controller

   Clear the codes. If the fault persists after sensor replacement and wiring verification, there is a functional failure in the controller (ECM/DEPR), and the controller itself must be replaced.