Hyundai Elantra: SRSCM / Occupant Classification System(OCS)
Description and operation
1. | In order to make normal activation of airbag system, SRSCM detects DTC(s) for the Occupant Classification System (OCS). If the seat is occupied, OCS detects passenger presences status and send signal to SRSCM via CAN. |
2. | SRSCM recognizes the signal as 2(two) different classifications; that is, 1(Empty or small occupant with child restraint system), 2(Occupied with large occupant and small occupant). |
3. | With these signal, ACU determines whether it needs to deploy the PAB(Passenger Airbag) or not. |
Components and components location

1. Occupant Classification System (OCS) Unit
| 2. Occupant Classification System (OCS) Sensor
|
Occupant Classification Sensor Unit


Pin no
|
Name
|
1
| ALR (-)
|
2
| ALR (+)
|
3
| Ground
|
4
| CAN (Low)
|
5
| CAN (High)
|
6
| IGN1
|
Repair procedures
Occupant Classification System (OCS)
1. | Disconnect the negative (-) battery terminal. •
| Disconnect the battery negative cable, and wait for at least three minutes before beginning work. |
|
|
2. | Remove the passenger's side front seat assembly. (Refer to Body (Interior and Exterior) - "Front Seat Assembly") |
3. | Remove the passenger seat cushion assembly. (Refer to Body (Interior and Exterior) - "Front Seat Cushion Cover") |
4. | Disconnect occupant classification sensor unit connector (A). 
|
5. | Remove the occupant classification sensor unit (A) after removing the clip. 
|
Occupant Classification System (OCS)
1. | Install the occupant classification sensor unit in the passenger seat track assembly. |
2. | Connect the occupant classification sensor unit connector. |
3. | Install the passenger seat cushion assembly. (Refer to Body (Interior and Exterior) - "Front Seat Cushion Cover") |
4. | Install the passenger's side front seat assembly. (Refer to Body (Interior and Exterior) - "Front Seat Assembly") |
5. | Reconnect the battery negative (-) terminal. |
6. | After installing the OCS, confirm proper system operation. •
| Turn the ignition switch ON the SRS indicator should be turned on for about 6 seconds and then go off. |
•
| Telltale lamp will turn on for 4 seconds and be turned off for 3 seconds. After the 7 seconds, it shall remain off if the OCS does not require suppression and the passenger airbag is enabled. |
•
| Be sure to perform OCS reset with diagnostic tool after replacing OCS equipped seat cushion. |
|
•
| After initializing the OCS sensor unit, erase DTC regarding the SRSCM and the OCS sensor unit. |
|
[DTC Manual]
DTC Code
| Code Name
| Description
| B1697(87)
| ACU Communication Error
| 1. ACU message cannot be received
| B1603(88)
| CAN BUS OFF
| 1. Vehicle CAN BUS bad reception
| P1680(87)
| VS Communication Fault
| 1. Vehicle speed message cannot be received
| P1681(81)
| VS Message Failure
| 1. Recive vehicle speed error signal
| B1111(17)
| Ignition Voltage High
| 1. High voltage condition (18.1V over)
| B1112(16)
| Ignition Voltage Low
| 1. Low voltage condition (6.7V under)
| B1763(00)
| OCS ECU Defect
| ECU internal element failure or S/W failure
| B1496(54)
| OCS Not Calibrated
| 1. Sheet factory zero adjustment process missing
| B1499(07)
| ALR Defect
| 1. ALR broken
|
|
OCS Reset procedure
You should perform OCS Reset procedure after service or replacement about all part of the passenger seat. (Not included full seat assembly)
1. | Ignition "OFF", connect GDS. |
2. | Ignition "ON" & Engine "OFF", select S/W Management and "Car model". |
3. | select OCS and "Body Sensor Reset". 
|
4. | Perform the "Body sensor reset" procedure according to the GDS screen message. |
Description and operation
Description•
The SRSCM should detect the condition of seat belt buckles (BS) of the driver and passenger seats...
Other information:
Blade type fuse
Cartridge type fuse
1. Turn the engine off.
2. Turn all other switches OFF.
3. Remove the fuse panel cover by
pressing the tap and pulling up.
4. Check the removed fuse; replace it
if it is blown. To remove or insert the
fuse, use the fuse puller in the engine
compartment fuse panel.
5. Push in a new fuse of the same
rating, and make sure it fits tightly in
the clips. If it..
Fuel Pressure Test1.Release the residual pressure in fuel line.(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
•
When removing the fuel pump fuse, a Diagnostic Trouble Code (DTC) may occur. Delete the code with the diagnostic tool after completion of "Release Residual Pressure in Fuel Line" work.2.Install the Special Service Too..