BMW 5251 Service Manual page 460

130-70
Fuel Injection
ECM
relay
- -
CAUTION-
Relay positions can vary Be sure to confirm relay position by
identifying the wiring in the socl(et using the wiring diagrams
in ELE Electrical Wiring Diagrams.
Working in right rear of engine compartment:
Release interior ventilation filter cover latch (A) and re-
move cover.
Release plastic locking tab (B).
Rotate duct inward (arrow) to unlock from bulk head and
remove duct.
Release spring loclt ( C ) to remove lower filter housing.
Slide filter housing away from inner fender to remove.
-
Remove electrical box (E-box) cover fasteners and remove
cover.
4
With ignition off, remove main relay (arrow) in electronics
box (E-box) at right rear of engine compartment.
NOTE-
Relay locations can vary Confirm relay identification by
matching wiring colors and terminal numbers.
4
Check for voltage at terminal
6
of main relay socket (30-red
wire).
If battery voltage is present, continue testing.
If battery voltage is not present, check large red wire in re-
lay socltet. See ELE Electrical Wiring Diagrams.
-
Reinstall relay and turn ignition on. Gain access to underside
of relay socket and check for ground at terminal 4 (85-brown
wire).
If ground is present, continue testing.
If ground is not present, switched ground signal from ECM
is missing. Check wire between ECM and relay.
-
With ignition on and relay installed, check for battery voltage
at terminal 2 (87-redlwhite wire).
If battery voltage is present, relay has energized and is
functioning correctly.
If battery voltage is not present and all earlier tests are OK.
relay is faulty and should be replaced.