AVL AVL DiCom 4000, Service Manual

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4-/5-Gas Measuring Instruments Unit AVL 4000
5-16 Service Manual
Primary error symptom Primary cause
(of error)
Secondary cause of
error Possible tests/
establishing cause Remedy
Faulty measuring
instruments unit ES in service mode
not 000000 Replace measuring
instruments unit
Faulty pump Short circuit
Interference Self-test when
pump switched on
or during zeroing Replace pump
Faulty pump cable
(465) Pump cable abraded
or worn Self-test when
pump switched on
or during zeroing Insulate cable
Use edge protectors
Electrical
interference (EMC) Faulty vehicle
ignition cable
Faulty ignition
Software error Radio or telephone
interference?
Are there sparks?
Ignition interference
in vehicle?
Very damp
atmosphere?
Radioing equipment
in the vicinity? Try placing the
instrument
somewhere else
Mains voltage
fluctuation Less than 180,
greater than 265 V
Mains too weak Other equipment
being operated, e.g.
dynamometer, large
fan Connect instrument
to another mains
phase
Self-test
Restart after O
2
sensor activated
Electronics fault or
faulty O
2
sensor
Test O
2
sensor
5…15 mV
or zeroing (ok)
→
exhaust gas (ok)
→
air incorrect O
2
value
Replace measuring
instruments unit
Replace O
2
sensor