Lexus SC300 / Lexus SC400. Manual - part 280

IN–33

).

WIRING DIAGRAM

Tc Terminal Circuit

CIRCUIT DESCRIPTION

Connecting between terminals Tc and E1 of the DLC1 or the DLC2 causes the ECU to display the diagnos-
tic trouble code by flashing the ABS warning light.

DIAGNOSTIC CHART

DIAGNOSTIC CHART

BR–148

–

BRAKE SYSTEM

ANTI–LOCK BRAKE SYSTEM (ABS)

NG

OK

OK

NG

INSPECTION PROCEDURE

1

Check voltage between terminals Tc and E1 of DLC2 or DLC1.

C

OK

P

Turn ignition switch ON.

Measure voltage between terminals Tc and E1 of DLC2
or DLC1.

Voltage:

10 – 14 V

If ABS warning light does not blink even after Tc and E1
are connected,t he ECU may be defective.

2

Check for open and short in harness and connector between ABS (& TRAC) ECU and DLC2 or
DLC1, DLC2 or DLC1 and body ground (See page 

IN–33

).

Repair or replace harness or connector.

Check and replace ABS (& TRAC) ECU.

–

BRAKE SYSTEM

ANTI–LOCK BRAKE SYSTEM (ABS)

BR–149

 

IN–33

).

WIRING DIAGRAM

Ts Terminal Circuit

CIRCUIT DESCRIPTION

The sensor check circuit detects abnormalities in the speed sensor signal which can not be detected with
the diagnostic trouble code check.Connecting terminals Ts and E1 of the DLC1 in the engine compartment
starts the check.

DIAGNOSTIC CHART

DIAGNOSTIC CHART

BR–150

–

BRAKE SYSTEM

ANTI–LOCK BRAKE SYSTEM (ABS)

NG

OK

OK

NG

INSPECTION PROCEDURE

1

Check voltage between terminal Ts and E1 of data link connector 1.

C

OK

P

Turn ignition switch ON.

Measure voltage between terminals Ts and E1 of DLC1.

Voltage:

10 – 14 V

If ABS warning light does not blink even after Ts and E1
are connected, the ECU may be defective.

2

Check for open and short in harness and connector between ABS (& TRAC) ECU and DLC1,
DLC1 and body ground (See page 

IN–33

).

Repair or replace harness or connector.

Check and replace ABS (& TRAC) ECU.

–

BRAKE SYSTEM

ANTI–LOCK BRAKE SYSTEM (ABS)

BR–151