Fault code 0087: Diagnosis/troubleshooting

NOTE: Visual inspection: In the next troubleshooting section, please check first that the affected pins on the KESSY control module plug connection are neither damaged nor corroded. The wiring and plugs of the affected components must also be checked for external damage and correct contacts. Repair damaged or corroded pins if possible, otherwise replace affected pins. Repair or replace damaged wires.

NOTE: Sporadic faults: In the event of faults that occur sporadically, the wiring positions that are linked to moving parts on and in the vehicle must be checked for each system. Various statuses that can cause faults must be simulated with the help of the wiring diagram.

NOTE: Battery voltage and signals: A battery voltage of between 11.4 and 14.5 V is required for the following troubleshooting procedure. This must be checked and provided, if necessary. Both signals and voltages as well as components or fuses (input side) must be guaranteed on the vehicle electrical system.

DIAGNOSIS/TROUBLESHOOTING CHART

Work instruction			Display OK	If not OK
1	Check fault type using [F8]		'Lower limit value not reached' Go to step 4 'Short circuit to ground/open circuit' Go to step 4 'Please read out fault memory' Go to step 2
2	Read out fault memory in vehicle electrical system control module		Further faults present => Correct the faults according to instructions	Go to step 3
3	Continue troubleshooting, refer to CHECKING INSTRUCTIONS/CAN DATA BUS .		→ End
4	Check fuse	Switch off ignition Remove fuse F41 (15A) from fuse carrier at left of dashboard and check it for continuity	Go to step 6	Go to step 5
5	Replace fuse		If fault is no longer present (fuse not faulty), see note on 'sporadic faults' → End	Fault still present (fuse faulty again) Go to step 8
6	Check input voltage at fuse	Measure voltage between fuse F41 (15A) 'on input side' in fuse carrier at left of dashboard and ground	Voltage is 11.4 to 14.5 V Go to step 7	Repair or replace wiring harness or components near fuse 'on input side' → End
7	Check wiring harness for voltage	Switch off ignition Pull off plug A on control module Insert fuse F41 (15A) in fuse carrier at left of dashboard Measure voltage between control module plug A, pins 5 and 1 Measure voltage between control module plug A, pins 5 and 2 Measure voltage between control module plug A, pins 4 and 1 Measure voltage between control module plug A, pins 4 and 2 Measure voltage between control module plug A, pin 1 and positive terminal of battery Measure voltage between control module plug A, pin 2 and positive terminal of battery	Voltage is 11.4 to 14.5 V Go to step 8	Repair line → End
8	Check wiring harness for short circuit to ground	Remove fuse F41 (15A) from fuse carrier at left of dashboard Measure resistance between control module plug A, pin 4 and ground Measure resistance between control module plug A, pin 5 and ground	∞ Ω Go to step 9	Repair line → End
9	Check wiring harness for open circuit	Measure resistance between fuse carrier at left of dashboard 'on output side' and control module plug A, pin 5 Measure resistance between fuse carrier at left of dashboard 'on output side' and control module plug A, pin 4 Measure resistance between control module plug A, pin 1 and ground Measure resistance between control module plug A, pin 2 and ground	< 5 Ω Go to step 10	Repair line → End
10	Replace control module		→ End