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W201 Error Code
1 No fault found.
2 Throttle position switch - wide open throttle (WOT), signal faulty
3 Engine coolant temperature sensor faulty
4 Air flow sensor position potentiometer voltage illogical
5 Oxygen sensor signal illogical
6 Not used
7 TNA/TD signal (RPM) read by CFI control module
8 Altitude pressure signal from ignition control module illogical
9 Electronic hydraulic actuator (EHA) current faulty.
10 Throttle position switch - closed throttle position fault (idle)
11 Air injection system, open or short circuit
12 Absolute pressure values from EZL ignition control module are illogical or Exhaust gas recirculation temperature sensor
13 Intake air temperature reading is illogical
14 Vehicle speed signal read by CFI control module is illogical
15 Not used
16 Exhaust gas recirculation switchover valve, open or short circuit
17 Oxygen sensor is shorted to positive or ground
18 Current to idle control valve is illogical
19 Not used
20 Not used
21 Not used
22 Oxygen sensor heater voltage illogical
23 Short circuit to positive in purge switchover valve circuit
24 Not used
25 Short circuit to positive in start valve circuit
26 Short circuit to positive in upshift delay solenoid valve circuit
27 Data exchange between CFI control module and ignition control module interrupted
28 Intermittent contact in engine coolant temperature sensor circuit
29 CFI and ignition control module reading different engine coolant temperatures - Faulty sensor or wires
30 Not used
31 Intermittent contact in engine coolant temperature sensor circuit
32 Not used
33 Not used
34 Engine coolant temperature read from ignition control module illogical

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1990 190E 3.0L