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SUPPLEMENTARY RESTRAINT SYSTEM (SRS)
17
ON VEHICLE SERVICE
ECU Replacement Procedure
Airbag ECU needs to be replaced in service only
when the following logged DTCs are confirmed as
per vehicle RCM troubleshooting guideline
(i)
B1650: Crash Recorded in 1st stage only
(ii)
B1651: Crash Recorded Side Airbag front-
driver
(iii)
B1652: Crash Recorded Side Airbag Front-
Passenger
(iv)
B1655: Crash recorded – Pass side with PAB
inhibited (no deployment)
(v)
B1658: Maximum belt pretensioner crash de-
tection reached
(vi)
B1620: Internal fault- Replace the ACU
The ECUs removed from the vehicle must be sent to
TML QA team for analysis.
ECU replacement is performed by following steps
ECU REMOVAL
1. Disconnect the battery connections.
2. Remove the floor console assembly.
(For proce-
dure refer floor console removal in CAB section).
3.
Remove the centre utility bin from the centre fin-
isher.
(For procedure refer dashboard removal in
CAB section).
4. Remove the cup holder assembly from the centre
finisher.
(For procedure refer dashboard removal
in CAB section).
5. Loosen and remove the mounting nuts
(Two from
vehicle rear and one from SRS ECU’s left at the
vehicle front end)
and lift and remove the SRS
ECU from the vehicle.
6. Disconnect the electrical connection from the air
bag ECU and remove the ECU assembly,
7. Replace the existing Airbag ECU with the new
one (Compare the labels of both the ECUs. The
assembly number and part number of the both
the ECUs should be same.)
8. Fix the new ECU on the mounting studs and
tighten the mounting screws. Tightening torque
recommended is 6.9 Nm – 9.8 Nm
9. Connect the Airbag ECU connectors
10. Restore 12V Battery power supply to Airbag
ECU
11. Connect the service tool to vehicle OBD Con-
nector
12.Turn ON ignition, Clear DTCs and check for any
DTCs in the new ECU
13. Read ECU identification details
14. Read VIN (Vehicle Identification Number) from
IC or BCM or EMS
15. Write VIN
16. Write ECU data – Lock (Firing Disable) /Unlock
(Firing Enable)