AUTOMATIC TRANSMISSION
Fault finding - List and location of components23A
23A - 7V3 MR-372-J84-23A000$090.mif
AJ0 BVA
Vdiag No.: 04, 05AUTOMATIC TRANSMISSION
Fault finding - List and location of components
*LS: line pressure.
*EVS: sequence solenoid valve.Number Description
1Oil temperature sensor
2Clutch 1 solenoid valve
3Clutch 2 solenoid valve
4Clutch 3 solenoid valve
5LS* pressure regulation solenoid valve
6"EVS1"* shift solenoid
7"EVS2"* shift solenoid
8Converter lock-up and brake 1 solenoid valve
9Brake 2 solenoid valve
10 Clutch 1 solenoid valve pressure switch
11 Clutch 2 solenoid valve pressure switch
12 Clutch 3 solenoid valve pressure switch
13 Brake 1 solenoid valve pressure switch
14 Brake 2 solenoid valve pressure switch
MR-372-J84-23A000$090.mif
AUTOMATIC TRANSMISSION
Fault finding - Role of components
23A
23A - 9V3 MR-372-J84-23A000$135.mif
AJ0 BVA
Vdiag No.: 04, 05AUTOMATIC TRANSMISSION
Fault finding - Role of components
Role of main automatic transmission components
Automatic transmission computer:
The gearbox computer is used to manage the entire system.
Its role is to define the optimum operating mode for the automatic transmission (modify the torque transmitted to the
drive wheels by the automatic transmission), inform the driver (instrument panel, information display, buzzer) and
communicate with the other computers.
To carry out this function, the transmission computer takes account of:
–the operation of the gearbox,
–signals exchanged with other computers,
–driver requests.
Transmission oil temperature sensor:
Its role is to inform the automatic transmission computer of the transmission oil temperature.
Transmission input speed sensor:
Its role is to inform the automatic transmission computer of the turbine speed.
Transmission output speed sensor:
Its role is to inform the automatic transmission computer of the vehicle speed.
Brake light switch:
Its role is to inform the automatic transmission computer that the driver has depressed the brake pedal.
Multifunction switch:
Its role is to inform the automatic transmission computer of the gear lever position.
Shift-lock:
The role of this function is to lock the lever in position "P" and to immobilise the vehicle when stationary.
Solenoid valves:
The solenoid valves are fitted in the factory and cannot be removed from the hydraulic distributor to ensure optimum
gearbox operation, therefore they cannot be replaced separately.
The automatic transmission has two types of solenoid valve:
–2 "all or nothing" solenoid valves,
–6 "progressive" solenoid valves.
Of these 8 solenoid valves, 7 are used to control gear changes in automatic and manual modes, and one solenoid
valve controls the oil pressure in the automatic transmission hydraulic distributor.
Instrument panel display:
The purpose of this function is to manage the transmission of multiplex line signals required for the instrument panel
display.
On the instrument panel:
–a fault warning light,
–a message on the instrument panel in case of irregularity,
–an information display: gear lever position/gear engaged/brake pedal depressed indicator light/lever position in P
or N request indicator light.
On the gear lever:
–Position: P / R / N / D / M+/-,
–Shift-lock: lever lock.
MR-372-J84-23A000$135.mif
AUTOMATIC TRANSMISSION
Fault finding - Fault summary table
23A
23A - 26V3 MR-372-J84-23A000$360.mif
AJ0 BVA
Vdiag No.: 04, 05AUTOMATIC TRANSMISSION
Fault finding - Fault summary table
*signal: signal
*EVS1 = sequence solenoid valve 1
*EVS2 = sequence solenoid valve 2
*LS = line pressure regulation solenoid valveTool fault Associated DTC Diagnostic tool title
DF023710 Transmission oil temperature sensor circuit
DF038715 Turbine speed sensor circuit
DF067705 Lever position switch circuit
DF084C073 Multiplex network
DF0851753 EVS1* shift solenoid circuit
DF0861758 "ESV2"* shift solenoid circuit
DF091748 "LS"* pressure regulation solenoid valve circuit
DF093826 Manual sequential controls circuit
DF095928 Gear lever lock electromagnet circuit
DF097740 Converter lock-up
DF1085300 Effective average torque multiplex signal
DF171720 Vehicle speed sensor circuit
DF1785600 Accelerator pedal position
DF183C140 No UCH multiplex signal
DF186C100 No injection multiplex signal
DF230C415 Invalid vehicle speed multiplex signal
DF236725 Invalid engine speed multiplex signal
DF2384073 Invalid raw engine torque multiplex signal*
DF256730 Erratic gear jumping
DF273753 Clutch 1 solenoid valve circuit
DF274763 Clutch 2 solenoid valve circuit
DF275768 Clutch 3 solenoid valve circuit
DF2891840 Automatic transmission multiplex signal
DF290C121 Multiplexed ABS signal
DF298893 Gear shifts
DF300758 Brake 2 solenoid valve circuit
DF301751 Clutch 1 pressure switch circuit
MR-372-J84-23A000$360.mif
