Troubleshooting (Hyundai Sonata 4 2001-2012, petrol: Body: Security systems)

Checking the operation of the SRS indicator

1. If after the first turn of the ignition key to the position "ON" SRS indicator flashes 6 times and then goes out, the indicator and SRS system are normal.

The normal state of the system.

2. If the SRS indicator does not light up after the ignition is turned on, or is on or flashes continuously, the SRS system needs to be diagnosed.

Note: Even if the SRS ECU is unable to function normally, the SRS indicator light will remain on to indicate that there is no ignition switch supply voltage to the control unit, no internal operating voltage to the SRS system, or no connection to the control unit connector.

3. Diagnosis by the indicator of the SRS system:

A) When the ignition is turned on and the engine is started: if the number of previously detected system failures is less than 4, the SRS indicator will be constantly on for 6 seconds and then turn off.

b) When the ignition is turned on and the engine is started, or the vehicle is moving, if the number of previously detected system faults is greater than 5 or a current fault is detected, the SRS indicator will illuminate continuously.
Note: If the fault was intermittent and the symptom does not reappear, the SRS indicator will turn off.

System diagnostics with a tester

1. Turn the ignition key to position "OFF".

2. Connect the tester to the standard diagnostic connector located under the front panel with driver's side.

3. Turn the ignition key to the position "ON" and turn on the tester.

4. Read the trouble codes and diagnose the SRS system in accordance with the configuration of this car model.

5. If fault codes are found, replace the faulty system component, then clear the fault codes.

Caution: Never attempt to disassemble or repair any component of the SRS system.

6. If the tester determines that the system component is OK, although the DTC is present, then the malfunction may not be in the component, but in the SRS system wiring or connector.

Troubleshooting by Diagnostic Codes

Code No. B1111, B1112:

Battery voltage (too high or too low respectively).

Registration conditions: within 10 seconds, the battery voltage is greater than 16V or less than 10V.

Note: If fault codes B1111 or B1112 are present, the SRS warning light is on constantly. If the battery voltage returns to normal, the SRS warning lamp goes out automatically and the corresponding DTC is cleared.

Probable cause of failure:

1. Rechargeable battery.
2. Charging system.
3. Wiring or connector.

Codes B1346, B1347:

Driver front airbag circuit (too high resistance or too low resistance respectively).

Registration conditions: detected if the resistance in this circuit is out of range (too high (R > 6.0 ohm) or too low (R < 0,9)).

Probable cause of failure:

1. Driver front airbag module (electric fuse).
2. Spiral wire SRS.
3. Electronic control unit SRS.
4. Wiring or connector.

Code B1348:

Short circuit in the driver's front airbag circuit to "mass".

Registration conditions: short circuit detected (on "mass") in the igniter circuit of the airbag module.

Probable cause of failure:

1. Front airbag module (electric fuse).
2. Spiral wire SRS.
3. Electronic control unit SRS.
4. Wiring or connector.

Code B1349:

Short circuit in the driver's front airbag circuit to battery voltage.

Registration conditions: short circuit detected (to the battery voltage circuit) in the igniter circuit of the airbag module.

Probable cause of failure:

1. Front airbag module (electric fuse).
2. Spiral wire SRS.
3. Electronic control unit SRS.
4. Wiring or connector.

Codes B1352, B1353:

Passenger airbag circuit (too high resistance or too low resistance respectively).

Registration conditions: detected if the resistance in this circuit does not correspond to the permissible range (too high (R > 4.2 ohm) or too low (R < 1.0 ohm)).

Probable cause of failure:

1. Passenger frontal airbag module (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1354:

Short circuit in the front passenger airbag circuit on "mass".

Registration conditions: short circuit detected (on "mass") in the igniter circuit of the airbag module.

Probable cause of failure:

1. Passenger frontal airbag module (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1355:

Short circuit in passenger's frontal airbag circuit to battery voltage.

Registration conditions: short circuit detected (to the battery voltage circuit) in the igniter circuit of the airbag module.

Probable cause of failure:

1. Front airbag module (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Codes B1361, B1362:

Driver's Pretensioner Circuit (too high resistance or too low resistance respectively).

Registration conditions: detected if the resistance in a given circuit is out of range (too high (R > 4.7 ohm) or too low (R < 0.9 ohm)).

Probable cause of failure:

1. Seat belt pretensioner (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Codes B1367, B1368:

Passenger Pretensioner Chain (too high resistance or too low resistance respectively).

See codes B1361, B1362.

Codes B1363, B1369:

Short circuit in the seat belt pretensioner circuit (driver or passenger respectively) on "mass".

Registration conditions: short circuit detected (on "mass") in the igniter circuit of the seat belt pretensioner.

Probable cause of failure:

1. Seat belt pretensioner (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1364, B1370:

Short circuit in the seat belt pretensioner circuit (driver or passenger respectively) to a circuit with battery voltage.

Registration conditions: short circuit detected (to the battery voltage circuit) in the igniter circuit of the seat belt pretensioner.

Probable cause of failure:

1. Seat belt pretensioner (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Codes B1378, B1379:

Driver side airbag circuit (too high resistance or too low resistance respectively).

Registration conditions: found that the resistance in this circuit is out of range (too high (R > 4.2 ohm) or too low (R < 1.0 ohm)).

Probable cause of failure:

1. Side airbag module (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1380, B1384:

Short circuit in the side airbag circuit (driver or passenger respectively) on "mass".

Registration conditions:short circuit detected (on "mass") in the igniter circuit of the airbag module.

Probable cause of failure:

1. Side airbag module (electric fuse),
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1381, B1385:

Short circuit in the side airbag circuit (driver or passenger respectively) to the battery voltage circuit.

Registration conditions: short circuit detected (to the battery voltage circuit) in the igniter circuit of the airbag module.

Probable cause of failure:

1. Side airbag module (electric fuse).
2. Electronic control unit SRS.
3. Wiring or connector.

Codes B1382, B1383:

Passenger side airbag circuit (too high resistance or too low resistance respectively).

See codes B1378, B1379.

Code B1395:

Malfunction in the side impact sensor circuit.

Registration conditions: A malfunction has been detected in the side impact sensor circuit.

Probable cause of failure:

1. Side impact sensor.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1400, B1409, B1414:

Side impact sensor, driver's side (encoder defective, data bus communication not possible or wrong encoder data ID respectively).

Registration conditions:a malfunction has been detected in the side impact sensor circuit, communication with the sensor via the data bus is not possible, or the sensor data set ID does not match the template.

Probable cause of failure:

1. Side impact sensor.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1401, 1404:

Short circuit in the side impact sensor circuit (driver or passenger respectively) on "mass".

Registration conditions: short circuit detected (on "mass") in the side impact sensor circuit on the driver's side.

Probable cause of failure:

1. Side impact sensor.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1402, 1405:

Short circuit in the side impact sensor circuit (driver or passenger respectively) to the battery voltage circuit.

Registration conditions:short circuit detected (to the battery voltage circuit) in the side impact sensor circuit on the passenger side.

Probable cause of failure:

1. Side impact sensor.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1403, B1410, B1415:

Passenger Side Sensor (encoder defective, data bus communication not possible or wrong encoder ID respectively).

See codes B1400, B1409, B1414.

Code B1406, B1407:

Passenger presence sensor in the front seat (encoder defective or data bus communication not possible respectively).

Registration conditions: a malfunction has been detected in the front seat passenger presence sensor circuit or communication with the sensor via the data bus is not possible.

Probable cause of failure:

1. Passenger presence sensor in the front seat.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1511, B1513:

Short circuit in the seat belt buckle switch circuit (driver or passenger respectively) to the battery voltage circuit.

Registration conditions:short circuit detected (to the battery voltage circuit) in the switch circuit.

Probable cause of failure:

1. Seat belt switch.
2. Electronic control unit SRS.
3. Wiring or connector.

Code B1S12, B1514:

Short circuit in the seat belt switch circuit (driver or passenger respectively) on "mass".

Registration conditions: short circuit detected (on "mass") in the switch circuit.

Probable cause of failure:

1. Seat belt buckle switch.
2. Electronic control unit SRS.
3. Wiring or connector.

Codes B1515, B1516:

Seat Belt Switch Malfunction (driver or passenger respectively)

Registration conditions:seat belt sensor fault detected

Probable cause of failure:

1. Seat belt sensor.
2. Wiring or connector.

Codes B1620, B1650, B1651, B1652, B1657:

Electronic SRS control unit.

B1620 - internal failure of the SRS electronic control unit;
B1650 - recording the operation of the frontal airbag;
B1651 - recording the deployment of the driver's side airbag;
B1652 - recording of the operation of the passenger's side airbag;
B1657 - command to activate the seat belt pretensioner;

Registration conditions: the SRS-ECU hardware safety loop is not activated or one of the following system parameters has failed and should be checked periodically:

A) The functional readiness of the transistors for activating the electric ignition control circuit.

Note: If the SRS ECU hardware safety circuit is not activated, the SRS warning light will come on.

b) Sufficiency of the reserve of electric power for the operation of the components of the SRS system.
V) Safety sensor operability: detection of a defective circuit closure.
G) Reliability of built-in acceleration sensor signals.
d) The performance of the components of the SRS system.

Probable cause of malfunction: SRS electronic control unit.

Code B2500:

Malfunction of the SRS system indicator.

Registration conditions: if the SRS indicator starts flashing 6 seconds after starting the engine.

Probable cause of failure:

1. Fuses.
2. Indicator in the instrument cluster.
3. Wiring or connector.

Component Circuit Check

1. Preliminary operations:

A) Switch off the ignition.
b) Disconnect the cable from the negative battery terminal and wait at least 30 seconds.
V) Remove the driver front airbag module.
G) Disconnect the wiring connectors from the passenger frontal airbag module, side airbag modules, seat belt pretensioners, side impact sensors, frontal impact sensors, and front seat occupant presence sensor.
d) Disconnect the SRS ECU connector.

2. In the event of a fault code corresponding to a short circuit:

A) Check resistance and voltage (no short circuit "mass" or power circuit) between terminal H (+) connector on the side of the component and "weight" body. If the test result is correct, check the component with a tester.

Rated value:

Resistance: ‎∞ (open circuit)
Voltage: 0V

b) If the test result is not correct, replace the wiring. For the driver's front airbag, check the SRS coiled wire.

3. In the event of a DTC corresponding to an open circuit or abnormal resistance:

Attention: checking the ignition circuit (air bag module or seat belt pretensioner) made only using a special simulator connected to the connector instead of the component. Do not attempt to measure the ignition resistance directly.

Nominal values for electric igniter circuit (test with simulator):

Driver front airbag module: 1.6-4.1 ohm
Passenger's frontal airbag module: 1.8 -2.8 ohm
Side airbag module: 1.8 - 2.8 ohm
Seat belt pretensioner: 1.8-3.1 ohm
Seat belt pretensioner lock:

Belt fastened: 3600-4400 ohms
Belt not fastened: 900-1100 ohm
Front passenger presence sensor: 50 kOhm (when the weight detected by the sensor is more than 15 kg)