Mitsubishi 3000GT Service Manual page 851

SERVICE BRAKES - Anti-lock Braking System Troubleshooting
E-5 When diagnostic trouble code "51 VALVE RELAY" is displayed
[Explanation]
When the ignition switch is turned ON, the ABS
ECU switches the valve relay OFF and ON for
an initial check, compares the voltage of the signal
to the valve relay and valve power monitor line
voltage to check whether the valve relay operation
is normal. In addition, normally it monitors whether
0
0 2
---
.
1
3
and check the valve
Remove
relay.
IGNITION
When the valve relay is
checked, are the following
conditions found?
No. 85-No. 86: Resistance
value 60-120 Q
No. 30-No. 87a: Continuity
No. 30-No. 87: No continuity
When battery positive voltage
is applied between terminals
No. 86 and No. 85.
No. 30-No. 87: Continuity
No. 30-No. 87a: No continuity
Install the valve relay and re-
move the HU connector.
Is there continuity between HU
No. 8 and No. 7 terminals?
Connect the HU harness and
remove the ECU connector.
1 i
ECU
Is there continuitv between 1
harness side connector termi-
nal No. 22 and ground?
ABS ECU malfunction
TSB Revision
or not there is power in the valve power monitor
line since the valve relay is normally ON. Then,
if the supply of power to the valve power monitor
line is interrupted, this diagnostic trouble code will
be output.
Yes
No
Yes
Yes
Yes
t
No
Yes
Faulty harness in HU
Repair harness.
Repair harness.
I
Replace ABS ECU.