Fault effects

• Substitute value from model

INFORMATION 

Step 1 

• When the engine is started after the ignition has been switched off for more than 8 hours, the engine coolant, engine oil, intake air and ambient air temperatures are compared with each other.
• They may deviate from the calculated mean value (T160)  by only a certain amount (depending on the switch-off time).
• A suspected fault is set if the deviation is too large. However, the fault must still be confirmed in the second step.

Step 2 

• Within the first six minutes after ignition on, a check is performed to determine whether the following conditions were met:
  • Drive > 25 km/h (15 mph) for longer than 45 seconds in total
  • None of the four temperatures decreased too much (e.g. due to drive from a garage into a cooler environment)
• If all conditions were met, the fault is entered in the fault memory.
• If one of the conditions was NOT met, the diagnostic result is rejected and NO fault is entered in the fault memory.
• If the vehicle is NOT driven in compliance with the aforementioned conditions within 6 minutes after starting, the suspected fault is rejected and NO fault is entered in the fault memory.