Lamp Out Indicator: Testing and Inspection

Without trailer coupling

Lighting
switch through, visual inspection.

Faulty circuit
determine.

Lighting
switch off.

NOTE: The bulbs are monitored individually. With bulbs with lower power (watt) this is displayed as fault, with higher power no fault is displayed.

NOTE: For diagnoses on xenon headlamps, Headlamp

Bulbs
test.

Power of bulbs
Low beam (standard) H 1/55W
Low beam (xenon) D2R/35W
High beam (sedan) H 1/55W
High beam (coupe) H 7/55W
Fog lamps H 3/55W
Side lamp/parking lamp 5 W
Turn signal/side lamp (USA) 21/5 W
Turn signal lamp 21 W
Stop lamp 21 W
Rear fog lamp/parking lamp 21/4 W
Rear fog lamp 21 W
License plate lamp 5 W (Suffitte)
Reverse lamp 21 W

Bulbs in order
test wiring according to wiring diagram for open circuit or short circuit and proper contact.



With trailer coupling (up to approx. 2/94)

NOTE: The combination relay N10/2 is switched over to trailer operation by a signal from the trailer detection control module N28/1. It detects trailer operation by means of an electrical measurement at the stop lamps of the trailer.

A faulty turn signal bulb on the trailer is indicated by the turn signal indicator lamp flashing more rapidly. At the same time, the lamp failure indicator lights up.

1 To simulate trailer operation, connect a 12-volt 21 watt bulb to terminal 54 (stop light) and terminal 31 (ground) of the trailer socket.
2 Turn key to position "2" (ignition on).
3 Switch on turn signal light. Flashing frequency is faster than normal and the lamp failure indicator lights up.

With trailer coupling (as of approx. 3/94)

NOTE: The combination relay N10/2 is switched over to trailer operation by the trailer recognition microswitch (X58s1).

This microswitch switches power to the combination relay (N10/2) when the trailer plug makes contact for recognition of trailer operation.

A defective turn signal bulb on the trailer is indicated by the turn signal indicator lamp flashing more rapidly. Simultaneously the lamp failure indicator lights up.

NOTE: As of 09/95 this is no longer indicated by the exterior lamps failure warning lamp.

1 To simulate trailer operation insert a plug into the trailer socket.