The ground at terminal 4 is switched by
the ECM. The ECM harness must be
connected to check the switched ground
connection.
-
If no faults are found up to this
point, turn ignition key off. Using a
fused (14 gauge) jumper wire,
connect relay connector terminal
6
to terminal
2
. The fuel pump
should run.
If pump runs and all other tests
are as specified, fuel pump relay
is probably faulty.
If pump does not run, test fuel
pump operation as described in
160 Fuel Tank and Fuel Pump
.
CAUTION!
The jumper wire should be 1.5 mm
2
(14 ga.) and include an in-line fuse
holder with a 15 amp fuse. To avoid
fuse/relay panel damage from
repeated connecting and
disconnecting, also include a toggle
switch.
Fuel delivery and fuel pressure
Checking fuel delivery volume and fuel
pressure is a fundamental part of
troubleshooting and diagnosing the
engine management system. Fuel
pressure directly influences fuel
delivery. Procedures for measuring the
fuel pressure and fuel volume are
given in
160 Fuel Tank and Fuel
Pump
.
Relieving fuel pressure
Fuel Injection
http://ebahn.bentleypublishers.com/BMW/3/E46/Repair%20Manuals/1...
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Summary of Contents for 1999-2005 M3
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