B1412
| B1412 | 
 
  
  | Fault symptom | 
Idling speed does not increase when the radiator fan starts. The engine speed could drop causing it to stall.
| Measures | 
| 1. | Connect a BOB and a voltmeter. Select "ACT.OTHER FUNCT" on the diagnostics instrument and then "IDLING INCREASE". Check that the voltage is 0 V at "ON" and 12 V at "OFF". | |
| 2. | If that is not the case, check the cable between ICE connection 10 and MOTRONIC engine control module's pin 44 for any short circuit to positive voltage. | |
| 3. | Connect the ICE control module and ground pin 44 on the MOTRONIC engine control module. Measure with a voltmeter and repeat point 1. | |
| 4. | If the voltmeter shows 0 V, go to Service Manual 2.7 for fault-tracing in the engine control system. If the voltmeter shows a voltage which is not 0 V, continue with the fault-tracing in Service Manual 3.5 under section ICE. | |

 
     
		