Crankshaft speed sensor DDE 5.1

The inductive crankshaft position/rpm sensor is screwed in the transmission bell housing. A flywheel with 58 small gaps and one large gap that moves past the crankshaft/rpm sensor is located on the flywheel. The DDE control unit evaluates the resulting voltage signals for the purpose of calculating the engine speed.

Both control units require the engine speed signal. For this reason the master control unit sends the engine speed signal via the P_INK line to the slave control unit.

The speed sensor signal is used as a measured variable for:

• Exhaust-gas recirculation
  
• Checking start conditions
  
• Calculating start volume
  
• Start of injection control
  
• Checking switch-on conditions for air conditioning system
  
• Calculating limitation volume
  
• Calculating external delivery rate intervention
  
• Charge-air-pressure control
  
• Injection rate control
  
• Rail pressure control
  
• Idle speed control
  

Troubleshooting

The signal of the speed sensor is monitored by the DDE control unit for faults. If the signal fails, the engine switches off and will not restart.