Lexus RX300 (MCU15). Manual — part 366

I07394

MPX2

E8

ECM

I03364

Sliding Roof ECU

MPX1

DI–694

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

LEXUS RX300 (RM785E)

INSPECTION PROCEDURE

1

Check the communication circuit inside engine & ECT ECU.

PREPARATION:
Disconnect the connector ”E8” of engine & ECT ECU.
CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the engine & ECT ECU.

NG

2

Check the communication circuit inside sliding roof ECU.

PREPARATION:
(a)

Connect the connector ”E8”of engine & ECT ECU.

(b)

Disconnect the connector of sliding roof ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the sliding roof ECU

NG

I07395

MPX2 MPX1

Passenger Door ECU

I03366

Rear Right Door ECU

”R15”

MPX2

MPX1

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

DI–695

LEXUS RX300 (RM785E)

3

Check the communication circuit inside passenger door ECU.

PREPARATION:
(a)

Connect the connector of sliding roof ECU.

(b)

Disconnect the connector of passenger door ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the passenger door ECU.

NG

4

Check the communication circuit inside rear right door ECU.

PREPARATION:
(a)

Connect the connector of passenger door ECU.

(b)

Disconnect the connector ”R15” of rear right door ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the rear right door ECU.

NG

I19184

Double Lock Control Relay

MPX1

MPX2

I03366

Rear Left Door ECU

”R13”

MPX2

MPX1

DI–696

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

LEXUS RX300 (RM785E)

5

Check the communication circuit inside double lock control relay.

PREPARATION:
(a)

Connect the connector ”R15” of rear right door ECU.

(b)

Disconnect the connector of double lock control relay.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the double lock control relay.

NG

6

Check the communication circuit inside rear left door ECU.

PREPARATION:
(a)

Connect the connector of double lock control relay.

(b)

Disconnect the connector ”R13” of rear left door ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the rear left door ECU.

NG

I07396

MPX1 MPX2

Driver Door ECU

I19211

Theft Deterrent
ECU

MPX1

MPX2

–

DIAGNOSTICS

MULTIPLEX COMMUNICATION SYSTEM

DI–697

LEXUS RX300 (RM785E)

7

Check the communication inside driver door ECU.

PREPARATION:
(a)

Connect the connector ”R13” of rear left door ECU.

(b)

Disconnect the connector of driver door ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the driver door ECU.

NG

8

Check communication inside theft deterrent ECU.

PREPARATION:
(a)

Connect the connector of driver door ECU.

(b)

Disconnect the connector ”T5” of theft deterrent ECU.

CHECK:
Check the DTC.
OK:
Code B1214/14 or B1215/15 is not output.

OK

Replace the theft deterrent ECU.

NG