ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - System operation87G
87G-11V7 MR-372-J84-87G050$110.mif
UPC
Vdiag No.: 48, 4C
5 - Exterior lighting
The Protection and Switching Unit receives lighting requests from the UCH via the multiplex network.
The computer then switches the power relays:
–side lights,
–dipped headlights,
–main beam headlights,
–front fog light.
For the operation of this function and the role of the Protection and Switching Unit in the control of this function,
(see 80D, Lighting).
6 - Wiping - Washing
The Protection and Switching Unit receives wiping requests from the UCH via the multiplex network.
The computer then switches the power relays:
–low or high-speed windscreen wiper,
–headlight washers pump relay.
–The Protection and Switching Unit also receives the windscreen wiper park position signal. Using this signal the
computer can determine whether the blade is jammed, and decide whether to stop the wiper motor to protect it.
For the operation of this function and the role of the Protection and Switching Unit in the control of this function,
(see 85A, W ipers-Washing).
7 - Oil pressure detection
The Protection and Switching Unit receives the oil pressure sensor signal and distributes it over the multiplex
network.
8 - Reverse gear engaged signal
The Protection and Switching Unit receives the reverse gear engaged position sensor signal and distributes it over
the multiplex network.
ENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Command summary table87G
87G - 75V7 MR-372-J84-87G050$715.mif
UPC
Vdiag No.: 48, 4CENGINE COMPARTMENT CONNECTION UNIT
Fault finding - Command summary table
Tool command Diagnostic tool title
AC001Main beam headlights
AC002Dipped headlights
AC003Side lights
AC004Front fog lights
AC005Low-speed windscreen wiper
AC006High-speed windscreen wiper
AC008Compressor control
AC009Low-speed fan assembly
AC010High-speed fan assembly
AC011Rear screen de-icer
AC013Headlight washers relay
AC014Alternator regulation
AC016Test electrical supply circuits
MR-372-J84-87G050$715.mif
