RM35X0E _57 Power Source / Network _078518 NETWORKING _0388279 LIN COMMUNICATION SYSTEM C

NETWORKING  LIN COMMUNICATION SYSTEM  B2789  No Response from ID BOX  


DESCRIPTION

This DTC is stored when LIN communication between the certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) stops for 10 seconds or more.

DTC No. Detection Item DTC Detection Condition Trouble Area
B2789 No Response from ID BOX No communication between certification ECU (smart key ECU assembly) and ID code box (immobiliser code ECU) for 10 seconds or more.
·

ID code box (immobiliser code ECU)

·

Certification ECU (smart key ECU assembly)

·

Harness or connector



WIRING DIAGRAM

B445874E44
4.896,0.396 6.396,0.75 1.5,0.354 10 false from Battery 5.156,0.948 5.563,1.24 0.406,0.292 10 false 1 5.479,0.906 6.375,1.302 0.896,0.396 10 false ECU-B NO.2 4.875,1.073 5.281,1.365 0.406,0.292 10 false +B 4.771,2 5.177,2.292 0.406,0.292 10 false GND 5.167,1.885 5.573,2.177 0.406,0.292 10 false 5 4.229,1.469 4.635,1.76 0.406,0.292 10 false LIN1 4.042,1.323 4.448,1.615 0.406,0.292 10 false 2 2.146,1.323 2.552,1.615 0.406,0.292 10 false 13 0.938,2.365 1.344,2.656 0.406,0.292 10 false N156 0.927,2.531 2.458,3.073 1.531,0.542 10 false Certification ECU (Smart Key ECU Assembly) 0.667,3.479 2.698,3.708 2.031,0.229 10 false : LIN Communication Line 3.938,2.375 4.344,2.667 0.406,0.292 10 false N158 3.927,2.542 5.5,3.083 1.573,0.542 10 false ID Code Box (Immobiliser Code ECU) 1.844,1.469 2.25,1.76 0.406,0.292 10 false LIN

CAUTION / NOTICE / HINT

NOTICE:
·

When using the GTS with the ignition switch off to troubleshoot:

Connect the GTS to the vehicle, and turn a courtesy light switch on and off at 1.5 second intervals until communication between the GTS and vehicle begins.

·

Inspect the fuse for circuits related to this system before performing the following inspection procedure.

·

Before replacing the certification ECU (smart key ECU assembly) or immobiliser code ECU, refer to the entry and start system (for start function).



HINT:

When the communication between the ID code box (immobiliser code ECU) and certification ECU (smart key ECU assembly) stops, DTC B2785 is also stored.


PROCEDURE

1.CHECK FOR DTC
a.

Clear the DTCs.

Click herePower Source / Network>NETWORKING>LIN COMMUNICATION SYSTEM>DTC CHECK / CLEAR

Body Electrical > Entry&Start > Clear DTCs
50002 125

b.

Check for DTCs.

Click herePower Source / Network>NETWORKING>LIN COMMUNICATION SYSTEM>DTC CHECK / CLEAR

Body Electrical > Entry&Start > Trouble Codes
50001 125

Result:
Result Proceed to
DTC B2789 is output A
DTC B2789 is not output B



A

2.CHECK HARNESS AND CONNECTOR (ID CODE BOX [IMMOBILISER CODE ECU] - BATTERY AND BODY GROUND)

B

USE SIMULATION METHOD TO CHECK

Click hereGeneral>INTRODUCTION>HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS>HOW TO PROCEED WITH TROUBLESHOOTING


2.CHECK HARNESS AND CONNECTOR (ID CODE BOX [IMMOBILISER CODE ECU] - BATTERY AND BODY GROUND)
a.
B301231C34
1.521,0.25 1.969,0.5 0.448,0.25 0.729,1.604 1.229,1.354 true 2.688,1.604 2.188,1.354 true 0.073,0.063 0.385,0.26 0.313,0.198 10 false *a 0.542,1.563 0.854,1.76 0.313,0.198 10 false +B 1.583,0.292 2.052,0.51 0.469,0.219 10 false N158 2.74,1.552 3.052,1.75 0.313,0.198 10 false GND
*a Front view of wire harness connector
(to ID Code Box [Immobiliser Code ECU])


Disconnect the ID code box (immobiliser code ECU) connector.


b.

Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Connection Condition Specified Condition
N158-5 (GND) - Body ground Always Below 1 Ω



c.

Measure the voltage according to the value(s) in the table below.

Standard Voltage:
Tester Connection Condition Specified Condition
N158-1 (+B) - Body ground Always 11 to 14 V



Result:
Proceed to
OK
NG



OK

3.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU [SMART KEY ECU ASSEMBLY] - ID CODE BOX [IMMOBILISER CODE ECU])

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU [SMART KEY ECU ASSEMBLY] - ID CODE BOX [IMMOBILISER CODE ECU])
a.

Disconnect the N156 certification ECU (smart key ECU assembly) connector.


b.

Disconnect the N158 ID code box (immobiliser code ECU) connector.


c.

Measure the resistance according to the value(s) in the table below.

Standard Resistance:
Tester Connection Condition Specified Condition
N156-13 (LIN) - N158-2 (LIN1) Always Below 1 Ω



Result:
Proceed to
OK
NG



OK

REPLACE ID CODE BOX (IMMOBILISER CODE ECU)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR