Lexus SC300 / Lexus SC400. Service manual — part 772

–MEMO–

–

STEERING

STEERING COLUMN

SR–65

DTC

53

Short in Squib Circuit (Between P

+

Wire Harness

P

–

Wire Harness)

CIRCUIT DESCRIPTION

The squib circuit consists of the center airbag sensor assembly, (squib). It causes the SRS to deploy when the
SRS deployment conditions are satisfied.
For details of the function of each component, see FUNCTION OF COMPONENTS on page

RS–10

. Diagnostic

trouble code 53 is recorded when an short is detected in the P

+

wire harness and P

–

wire harness of the squib

circuit.

DTC No.

Diagnosis

53

Short circuit between P

+

wire harness and P

–

wire harness of squib.

Squib malfunction.

Center airbag Sensor Assembly malfunction.

DIAGNOSTIC CHART

DIAGNOSTIC CHART

RS–110

–

SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

WIRING DIAGRAM

DIAGNOSTIC CHART

DIAGNOSTIC CHART

–

SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING

RS–111

OK

NG

INSPECTION PROCEDURE

1

Preparation.

P

1.

Disconnect battery negative (–) terminal cable, and
wait at least 90 seconds.

2.

Remove steering wheel pad (See page

RS–19

).

3.

Disconnect connectors of front passenger airbag
assembly (See page

RS–32

).

Caution:

Store the steering wheel pad with the

surface facing upward.

2

Check P squib circuit.

C

OK

Measure resistance between P+ and P– on center air-
bag sensor assembly side of connector between center
airbag sensor assembly and front passenger airbag as-
sembly.

Resistance:

1 k

or higher

Go to step

.

RS–112

–

SUPPLEMENTAL RESTRAINT SYSTEM

TROUBLESHOOTING