FMI 5 – Current below normal or open circuit
Fault code explanation: Faulty sensor / Faulty sensor circuit
Fault indication: DCU: Engine warning in DCU display.
CIU: Flash code
Flash code
Electrical fault: 5.4
Value fault: None
Symptom: Preheat relay never activated. White smoke for cold start.Start problems in
cold climate.
Conditions for fault code: The current through pin B25 or through pin B7 on the EMS2 deviates from
normal current value.
Possible reason: Open circuit in cable harness between EMS2 and preheat relay.
Suitable action: 1 Check all connections on the preheat relay and all cables between
EMS2 and preheat relay.
2 Check the contact pressure in socket 25 and in socket 7 in the engine
connector B.
Circuit description
In cold climate the intake air might need too be pre-
heated. This is done by the preheater located on the
intake manifold.
The activation of the preheater is con-
trolled by the EMS2 via the preheat relay. EMS2 pin
B25 activates the preheat relay. A sense wire is con-
nected between the preheater relay output and B7.
The sense wire checks that the preheat element and
the preheat fuse are not damaged.
Measurements
Checking the wiring page 141
p0013470
EMS2
A
C
B
25
60
7
(+)57,
OR
R / BL
BN
p0013471
A Connector B
B
Junction point
C
Preheat relay
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