| 1 |
Fault code |
P0400 |
| 2 |
Fault storage |
after expiry of test duration and fault |
Actuation of the engine diagnosis indicator lamp (EURO3/4)
or CHECK ENGINE (MIL) malfunction indicator lamp  |
after two successive driving cycles with faults |
| 3 |
Checking frequency |
once per driving cycle |
| 4 |
Checked signal or status |
A. Intake manifold pressure
B. Misfire detection in EURO3/4 |
| 5 |
Fault setting conditions
Checking duration |
A. The intake manifold vacuum must decrease by at least 54 mbar with exhaust gas recirculation
B. Misfiring must be detected at idle speed for active exhaust gas recirculation.
Approx. 2 s |
| 6 |
Check prerequisites
A.
B. EURO3/4 |
- No fault on electrical control EGR vacuum transducer (Y31/1)
- No fault on intake manifold pressure sensor (B28)
- Inertia fuel shutoff active
- Coolant temperature > 80 °C
- Air pressure more than approx. 780 hPa (i.e. no test is performed above a height of approx. 2500 m)
- neutral
- No fault at smooth-operation analysis
|
| 7 |
After a repair, carry out test and driving instructions
A. |
- Warm up engine
- Drive vehicle and accelerate to approx. 2000 rpm
- Then let vehicle decelerate in deceleration mode up to approx. 1100 rpm. If the test is performed, this is displayed in the HHT as follows: If the test is passed without a fault, "-V-" is placed in dark (repair is successful). If the test is passed with a fault, "-F-" is placed in dark. After ignition OFF the tests are again restored (white field). Only after the test has been performed once again, the corresponding fields are once again placed in dark.
Carry out a new test only after approx. 10 seconds ignition OFF. |
| 8 |
 |
If the prerequisites exist, the intake manifold pressure is measured and exhaust gas recirculation is then briefly activated.
- In engine 112 EURO3/4 exhaust gas recirculation testing is carried out through smooth operation evaluation.
|