| Test | TECH 1 | Notes | Nominal Values | Pin | Possible |
|---|---|---|---|---|---|
| Step | Display | Trouble | |||
| No. | Codes | ||||
| 10 | ENGINE LOAD SIG. | Engine at idle speed, | MY '90: | 34/19 | 73, 74 |
| operating temperature | MT: 1.6 to 2.4 ms | 19, 31 | |||
| AT: 1.8 to 2.5 ms | |||||
| MY '89: | |||||
| MT: 1.8 to 2.4 ms | |||||
| AT: 1.9 to 2.5 ms |
Note:
The engine load signal Ter. 34 (output signal) is a processed throttle valve potentiometer signal which is used for the ele- ctronic 4-speed Automatic AR 25/35 or AF 14/20 as an influencing variable.
The throttle valve potentiometer is the only influencing variable on the signal.
Possible Causes of Fault:
· Air leaks in the intake system.
· Air flow meter defective; trouble codes 73, 74.
· Engine speed sensor signal faulty: trouble codes 19, 31.
· Cable connection from throttle valve potentiometer P 34/Ter. 3 to control unit K 91/Ter. 53 or from Motronic control unit K 91/Ter. 34 to transmission control unit Ter. 55 (AR 25/35) or Ter. 25 (AF 14/20) interrupted.
· Motronic control unit defective