Chart B-5 Excessive Isolation Time (Dtc 18 (Flash Out) / C0274 (Serial Communications)); Chart B-6 G-Sensor Output Failure (Dtc 21 (Flash Out) / C0276 (Serial Communications)); Chart B-7 Brake Switch Failure (Dtc 22 (Flash Out) / C0281 (Serial Communications)) - Isuzu 1999 RODEO Workshop Manual

BRAKE CONTROL SYSTEM
5A–42

Chart B-5 Excessive Isolation Time (DTC 18 (Flash out) / C0274 (Serial communications))

Step
1 Check for anything causing extended ABS activation, such as
locked brakes or an erratic speed sensor signal.
Was a problem found?
2 1. The key turned off.
2. Replace EHCU.
3. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?

Chart B-6 G-Sensor Output Failure (DTC 21 (Flash out) / C0276 (Serial communications))

Step
1 1. Turn the key off.
2. Replace EHCU.
3. Reconnect all components, ensure all components are
properly mounted.
Was this step finished?

Chart B-7 Brake Switch Failure (DTC 22 (Flash out) / C0281 (Serial communications))

Step
1 Is the stop light actuated when the brake pedal is depressed?
2 1. Turn the key off.
2. Disconnected coil integrated module connector.
Is the check voltage coil integrated module connector (C-4)
terminals 13 to 7 when brake pedal is depressed than battery
voltage?
3 Is the check that pins C-5 connector 2, and C-4 connector 7 have
good ground?
4 Is stop light fuse normal?
5 Is brake SW normal?
6 1. Reconnect all components, ensure all components are
properly mounted.
2. Clear diagnostic trouble code.
Was this step finished?
Action
Action
Action
Yes
Repair or
Replace Go to Step 2
Repeat the "Basic
diagnostic flow
chart" Go to Step 2
Yes
Repeat the "Basic
diagnostic flow
chart" Go to Step 1
Yes
Go to Step 2 Go to Step 4
Harness between
brake SW and
coil integrated
module is faulty.
Go to Step 6
Go to Step 3
Check harness /
connector for
disconnection
Fault found:
Repair, and
perform system
self-check.
No fault found:
replace EHCU.
Go to Step 6
Go to Step 6
Go to Step 5
Go to Step 6
Abnormal
harness in stop
light circuit.
Repair the
harness.
Go to Step 6
Go to Step 6
Repeat the "Basic
diagnostic flow
chart"
Go to Step 6
No
No
No
Repair.
Replace.
Replace.