E-Tempomat System

Fig. 1 Coding Plug Terminal Identification:

1. Disconnect coding plug from cruise control control unit. On 190D and E models, the control unit is attached to a plate located in the right hand front foot well. On all other models, the control unit is located under the left hand side of the instrument panel.
2. Using a suitable ohmmeter measure resistance between coding plug terminals A and D, Fig. 1. An infinite reading should be obtained.
3. Connect ohmmeter between terminals B and E. A reading of 1470k to 1530k ohms should be indicated.
4. Connect ohmmeter between terminals D and C. A reading of .01 to 15 ohms should be indicated.
5. Connect ohmmeter between terminals D and H. A reading of 3.21k to 3.27k ohms should be indicated for coring plug part No. 005-545-07-32. For coding plug part No. 005-545-08-32, reading should be between 1.18k to 2.02k ohms.
6. Connect ohmmeter between terminals E and D. An infinite reading should be indicated.
7. Connect ohmmeter between terminals E and F. A reading of 26.2k to 27.2k ohms should be indicated for coding plug part No. 005-545-07-32. For coding plug part No. 005-545-08-32, reading should be between 25.2k to 27.2k ohms.
8. Connect ohmmeter between terminals E and G. A reading of 501k to 521k ohms should be indicated.
9. If ohmmeter readings are as specified above, replace coding plug.