Page 4062 of 4264
7A2-70 DIAGNOSIS (JR405E)
Step Action Yes No
1 Clear the DTC from the memory once.
Was the action complete?
Go to Step 2
Refer DTC clear
method in this
manual.
2 Turn the ignition switch off once, then restart the engine and in D
range. When about 10 seconds elapsed, does the CHECK TRANS
lamp blink?
Go to Step 3 Go to Step 7
3 Is the DTC P0758 (32) 2-4 Brake Duty Solenoid Failure stored?
Go to P0758 (32)
Section Go to Step 4
4 Connect the Tech 2 and select the item for 2-4 brake pressure
switch. Is the indication of 2-4 brake pressure switch turned off when
the terminal assembly connector is disconnected?
Go to Step 5
Repair the harness
or connector.
Go to Step 12
5 Turn the key switch off and disconnect the terminal assembly
connector. Are the pins correct?
Go to Step 6
Repair the
connector or pin.
Go to Step 12
6 Remove the oil pan. Is the continuity correct between terminal
assembly terminal 7 and 2-4 brake pressure switch connector?
7
Repair the harness
or connector.
Go to Step 12
Replace pressure
switch.
Go to Step 12
7 Start the engine and shift to 4th gear in the D range. When about 10
seconds elapsed, does the CHECK TRANS lamp blink?
Go to Step 8
Go to P0758 (32)
Section
8 Connect the Tech 2, and with the key switch in OFF position, short
the terminals 11 and 7 on the vehicle harness side. Does the
indication of the 2-4 brake pressure switch on the Tech 2 becomes
on when the key switch is turned on?
Go to Step 9
Repair the harness
or connector.
Go to Step 12
Page 4063 of 4264
DIAGNOSIS (JR405E) 7A2-71
Step Action Yes No
9 Check if the trouble is caused by a poor connection of terminal
assembly connector.
With the key switch in OFF position, is the connection condition of
the connector and harness correct?
Go to Step 10
Repair the harness
or connector.
Go to Step 12
10 Remove the oil pan. Is the continuity correct between terminal
assembly terminal 7 and 2-4 brake pressure switch connector?
7
Go to Step 11
Repair the harness
or connector.
Go to Step 12
11 Is the result OK when the oil pan is removed and the 2-4 brake
pressure switch is checked? Repair the control
valve.
Go to Step 12
Replace pressure
switch.
Go to Step 12
12 Clear the DTC from the memory and perform the work after repair. Is
the same DTC code outputted again in the subsequent DTC check?
Replace the TCM Go to Step 13
13 Are the other DTCs outputted?
Go to Other DTC
Section Action is completed
Page 4064 of 4264
7A2-72 DIAGNOSIS (JR405E)
DTC P1863 (Flash Code 28) High Clutch Pressure Switch Failure
Control Valve
TCM
B1
B12
B20
RED/YEL
WHT/BLK
2-4 Brake Pressure SW
Terminal
Assembly
YEL
E54 (7)
(12)
(1)H23 (12)
(10)C95 (1)
(12)
(20)
RED/YEL
YEL
WHT/BLK
L&R Brake Pressure SW
High Clutch Pressure SWH22 (8)
Pre-setting Condition:
No gear shifting.
No Check Trans indicator lamp.
No system voltage failure.
No inhibitor switch failure.
2-4 brake duty solenoid 0 or 100 %.
ATF temperature more than 60 C.
ATF input voltage more than 0.1V.
Engine speed more than 500 rpm.
Page 4065 of 4264
DIAGNOSIS (JR405E) 7A2-73
Setting Condition:
During the running, the high clutch pressure switch does not turn on though hydraulic pressure is supposed to be
generated in high clutch.
(All pre-setting conditions are met for 2.5 seconds, high clutch pressure switch off, 2-4 brake pressure switch on
and gear ratio more than 0.65 or less than 0.74 with 4th gear in D range.)
Or
During the running, the high clutch pressure switch does not turn off though no hydraulic pressure is supposed
to be generated in the high clutch.
(All pre-setting conditions are met for 2.5 seconds, high clutch pressure switch on in P, R or N range.)
Fail Safe:
No fail safe function
Possible Cause:
High clutch duty solenoid malfunction.
High clutch pressure switch open circuit or short circuit.
Open circuit, short circuit to battery or short circuit to ground of the harness between high clutch pressure switch
terminal 1 and TCM terminal B20 (C95).
High clutch hydraulic circuit malfunction in the control valve.
Poor connection of each connector.
Reference:
When the high clutch pressure switch is operated, following signal is outputted.
Measurement terminal: B20 (C95) and B22 (C95)
-At other than 3rd or 4th gear: More than 10V
-At 3rd or 4th gear: Less than 1V
Page 4069 of 4264
DIAGNOSIS (JR405E) 7A2-77
Step Action Yes No
6 Is the quantity of ATF correct?
Go to Step 7
Correct the quantity of
ATF.
Go to Step 9
7 Connect the Tech 2 and test the solenoids of respective
solenoids for low & reverse brake, 2-4 brake, high clutch and
low clutch. Is operation sound heard from each solenoid?
Go to Step 8
Replace the solenoid
that does not generate
the operation sound.
Go to Step 9
8 Check the line pressure during the idling and at the engine stall
speed. Is the line pressure correct?
Go to Step 10
Either control valve, oil
pump or power train
parts (clutch, brake)
will be faulty. Replace
or overhaul the
transmission unit.
Go to step 10
9 Run the vehicle, and is the gear shifted from 1st to 4th
correctly?
Go to Step 10
Either control valve, oil
pump or power train
parts (clutch, brake)
will be faulty. Replace
or overhaul the
transmission unit.
Go to step 10
10 Clear the DTC from the memory and perform the work after
repair. Is the same DTC code outputted again in the
subsequent DTC check?
Replace the TCM Go to Step 11
11 Are the other DTCs outputted?
Go to Other DTC
Section Action is completed
Page 4070 of 4264
7A2-78 DIAGNOSIS (JR405E)
DTC P1750 (Flash Code 51) Low & Reverse Brake Fail-safe Valve Failure
Low & Reverse Brake Fail Valve (B)Control Valve Upper Body
Low & Reverse Brake Fail Valve (A)Control Valve Lower Body
Setting Condition:
When the oil pressure generated and low & reverse brake pressure switch operates off/on twice, the TCM
detected an operation failure of the low & reverse brake fail-safe valve in D, 3, 2, L range.
Fail Safe:
When the vehicle is running, the gear position selected at the trouble detection is held and the lock-up is
inhibited.
After the vehicle stopped, all solenoid operations stop (OFF) and the gear is fixed to the 3rd.
Possible Cause:
Stick of low & reverse brake fail-safe valve.
Low & reverse brake pressure switch does not turn on.
Short circuit to ground of harness low & reverse brake pressure switch.
Poor connection of each connector of harness in low & reverse brake pressure switch.
Page 4071 of 4264
DIAGNOSIS (JR405E) 7A2-79
Step Action Yes No
1 Turn the key switch on and check the DTC. Is only the DTC for
low & reverse brake fail-safe valve failure outputted?
Go to Step 2
Go to Other DTC
Section
2 Clear the DTC from the memory. Turn the key switch off once,
and then start the engine. Does the CHECK TRANS blink
when the D range is selected and about 10 seconds elapsed?
Go to Other DTC
Section Go to Step 3
3 Run the vehicle, shift the gear from 1st to 4th, stop the vehicle,
and again shift the gear from 1st to 4th. Does the CHECK
TRANS blink at this time?
Go to Step 4
The low & reverse
brake fail-safe valve
may be faulty
temporarily.
Go to step 5
4 Turn the key switch on and check the DTC. Is only the DTC for
the low & reverse brake fail-safe valve failure outputted?
Repair or replace the
control valve.
Go to Step 5
Go to Other DTC
Section
5 Clear the DTC from the memory and perform the work after
repair. Is the same DTC code outputted again in the
subsequent DTC check?
Replace the TCM Go to Step 6
6 Are the other DTCs outputted?
Go to Other DTC
Section Action is completed
Page 4072 of 4264
7A2-80 DIAGNOSIS (JR405E)
DTC P1755 (Flash Code 52) 2-4 Brake Fail-safe Valve Failure
Control Valve Upper Body2-4 Brake Fail Valve (B)
Control Valve Lower Body2- 4 Br ake Fai l Val ve ( A)
Setting Condition:
When the oil pressure generated and 2-4 brake pressure switch operates off/on twice, the TCM detected an
operation failure of the low & reverse brake fail-safe valve in D, 3, 2, L range.
Fail Safe:
When the vehicle is running, the gear position selected at the trouble detection is held and the lock-up is
inhibited.
After the vehicle stopped, all solenoid operations stop (OFF) and the gear is fixed to the 3rd.
Possible Cause:
Stick of 2-4 brake fail-safe valve.
2-4 brake pressure switch does not turn on.
Short to ground of harness 2-4 brake pressure switch.
Faulty fitting of each connector of harness in 2-4 brake pressure switch.
