Testing with adapter - RA30001240504X(30-504)
Job No. of the job texts and work units and standard texts and flat rates
Special tool
Pre-requisite for testing
Prior to starting test with adapter, check battery voltage (> 11 V), stop lamps and speed indication for function. If required, recondition according to findings and also check cruise control/Tempomat prior to test for function by means of adapter. Test cruise control/Tempomat with adapter only.
If other testing and measuring instruments are used, the cruise control/Tempomat unit may be destroyed. During this test, the cruise control/ Tempomat unit is tested with the exception of the cruise control amplifier. Faults can be discovered by means of the adapter only with the cruise control/Tempomat constantly without function. Complaints such as a temporary breakdown or poor control characteristics (e.g. shaking) cannot be tested with the adapter. In such cases, proceed according to notes for trouble diagnosis 30.0101-502.
If testing with the adapter indicates a faulty component, pay attention to good contact-making qualities prior to exchanging connectors, for instance, making sure that the jacks (sockets) are not widened. Widened jacks should be reshaped. Then check rejected component once again.
Preparations for test
- Expose cruise control amplifier (refer to 30.0101-565).
- Pull 14-pole connector from amplifier.
- Connect test adapter to 14-pole connector.
- Switch on ignition. The LED displays of the symbols for battery, km/h and ground (if line according to wiring diagram is installed) will light up, provided no fault has been detected.
- Push "LED-TEST" push-button switch of test adapter and check whether all LED displays are lighting up. If no LED display is lighting up, check connection of voltage supply and circuit connections of 14-pole connector (refer to wiring diagrams 30.0101-580).
| Test step | Actuation | Nominal indication | Possible cause of deviation from nominal indication |
|---|---|---|---|
| 1 | LED display lighting up. |
Lines wrongly connected. Lines interrupted. | |
| LED display lighting up on models with grounding bridge. |
Grounding bridge in 14-pole connector interrupted. | ||
| LED display may light up. | Perform test step 6. | ||
| 2 | Actuate cruise control/Tempomat switch (position 1-4). | Respective LED display lighting up. | Lines interrupted. Switch defective. |
| 3 | Depress |
Regulating linkage moving uniformly to full throttle position and remains there. | Regulating linkage and accelerator pedal not moving: Connecting rod on cruise control actuator or on regulating linkage not connected. Lines interrupted or wrongly connected. Switch on clutch pedal defective. Actuator defective. Regulating linkage and accelerator pedal constantly moving to-and-fro: Poor contacting of plug connection harness/actuator harness. Throttle control and accelerator pedal not pulled to full throttle position: Check contacting of lines for actuator and amplifier (control unit). Actuator defective. |
| 4 | Depress |
Regulating linkage not moving immediately into idle speed position when brake pedal is actuated. | Regulating linkage sluggish. Actuator defective. |
| 5 Manual transmission only | Depress |
Regulating linkage moving immediately into idle speed position when clutch pedal is actuated. | Lines shorted. Switch on clutch pedal defective. |
| 6 | Move vehicle for at least 2 revolutions of wheels. | LED display flashing. | Lines interrupted or wrongly connected. Sensor defective. |
If no fault has shown up on previous test:
- Test blue line from connector cruise control actuator jack 5 to connector cruise control amplifier jack 10 for short to ground by means of ohmmeter.
- On amplifiers (control units) with reference resistor, test reference resistor R 29 (30.0101-506).
- Mount new cruise control amplifier (control unit) for test drive.
Testing