Opel Frontera UBS. Manual - part 2930

9J1–23

RESTRAINT CONTROL SYSTEM

DTC 21  Driver Deployment Loop Resistance High

D09RW014

Circuit Description:

When the ignition switch is turned “ON”, the SDM will
perform tests to diagnose critical malfunctions within
itself.  Upon passing these tests, “Ignition 1”,  and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges.
The SDM then proceeds with the “Resistance
Measurement Test” “Driver Bag Low” terminal “4” is
grounded through a current sink and the driver current
source connected to “Driver Bag High” terminal “3” allows
a known amount of current to flow.  By monitoring the
voltage difference between “Driver Bag High” and “Driver
Bag Low”, the SDM calculates the combined resistance
of the driver air bag assembly, SRS coil assembly,
harness wiring IB05–YEL and IB06–YEL/BLK, and
connector terminal contact.

DTC Will Set When:

The combined resistance of the driver air bag assembly,
SRS Coil assembly, harness wiring IB05–YEL and
IB06–YEL/BLK, and connector terminal contact is above
a specified value.  This test run once each ignition cycle
during the “Resistance Measurement Test” when:

1. No “higher priority faults” are detected during

“Turn–ON”

2. “Ignition 1” voltage is in the specified value.

Action Taken:

SDM turns “ON” the “AIR BAG” warning lamp and sets
DTC 21.

DTC Will Clear When:

The ignition switch is turned “OFF”.

DTC Chart Test Description:

Number(s) below refer to step number(s) on the
diagnostic chart:
2. This test determines whether the malfunction is in

the SDM.

3. This test verifies proper connection of the yellow

2–pin connector at the base of the steering column.

4. This test checks for proper contact and/or corrosion

of the 2–pin connector terminals at the base of
steering column.

5. This test isolate the malfunction to one side of the

SRS coil assembly yellow 2–pin connector located
at the base of the steering column.

6. This test determines whether the malfunction is due

to high resistance in the wiring.

7. This test determines whether the malfunction is in

the SRS coil assembly or the driver air bag
assembly.

RESTRAINT CONTROL SYSTEM

9J1–24

Diagnostic Aids:

An intermittent condition is likely to be caused by a poor
connection at terminals “1” and “2” of the SRS coil 2–pin
connector at the base of the steering column, terminal “1”
and “2” of the driver air bag assembly 2–pin connector at
the top of the steering column, SDM terminals “3” and “4”
or a poor wire to terminal connection in IB05–YEL or

IB06–YEL/BLK.  The test for this diagnostic trouble code
is only run while the “AIR BAG” warning lamp is
performing the bulb check, unless DTC 17 or DTC 26 is
detected.  When a scan tool “Clear Codes” command is
issued and the malfunction is still present, the DTC will not
reappear until the next ignition cycle.

DTC 21 Driver Deployment Loop Resistance High 

Step

Action

Yes

No

1

Perform the “SRS Diagnostic System Check”.

Was the “SRS Diagnostic System Check” performed?

Go to Step 2

Repeat the “SRS

Diagnostic

System Check”

2

1. When measurements are requested in this chart use

5–8840–0285–0 DVM with correct terminal adapter from
5–8840–0385–0. 

2. Use scan tool data list function, read and record the driver

deployment loop resistance.

Is driver resistance more than 3.7 ohms?

Go to Step 3

Go to Chart A

3

1. Ignition switch “OFF.”
2. Disconnect SRS coil assembly yellow 2–pin connector located

at base of steering column is seated properly.

Is the 2–pin connector connected properly?

Go to Step 4

Seat SRS coil

assembly 2–pin

connector

properly

Go to Step 8

4

1. Disconnect and inspect the SRS coil  assembly yellow 2–Pin

connector located base of steering column.

2. If ok, reconnect the SRS coil  assembly yellow 2–pin

connector.

3. Ignition switch “ON.”

Is DTC 21 current?

Go to Step 5

Go to Step 8

5

1. Ignition switch “OFF.”
2. Disconnect SRS coil and passenger air bag assembly, yellow

2–pin connector located at the base of steering column and
behind the glove box assembly.

3. Connect SRS driver / passenger load tool 5–8840–2421–0

and appropriate adapter to SRS coil  and passenger air bag
assembly harness  connectors.

4. Ignition switch “ON.”

Is DTC 21 current?

Go to Step 6

Go to Step 7

6

1. Ignition switch “Off.”
2. There has been a increase in the total circuit resistance of the

driver deployment loop.

3. Use the high resolution ohmmeter mode of the DVM while

checking IB05–YEL and IB06–YEL/BLK, and SDM connector
terminal “3” and “4” to locate the root cause.

Was a fault found?

Replace SRS

harness

Go to Step 8

Go to Chart A

9J1–25

RESTRAINT CONTROL SYSTEM

DTC 21 Driver Deployment Loop Resistance High  (Cont’d)

Step

No

Yes

Action

7

1. Ignition switch “OFF.”
2. Disconnect SRS driver / passenger load tool from SRS coil

assembly harness connector.

3. Connect SRS driver / passenger load tool 5–8840–2421–0 on

the top of steering column.

4. Reconnect SRS coil assembly harness connector as the base

of steering column.

5. Ignition switch “ON.”

Is DTC 21 current?

Ignition switch

“OFF”

Replace SRS coil

assembly

Go to Step 8

Ignition switch

“OFF”

Replace driver air

bag assembly

Go to Step 8

8

1. Reconnect all components ensure all component are properly

mounted.

2. Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic

System Check” 

Go to Step 8

RESTRAINT CONTROL SYSTEM

9J1–26

DTC 22  Driver Deployment Loop Resistance Low

D09RW014

Circuit Description:

When the ignition switch is turned “ON”, the SDM will
perform tests to diagnose critical malfunctions within
itself.  Upon passing these tests “Ignition 1”,  and
deployment loop voltages are measured to ensure they
are within their respective normal voltage ranges.
The SDM then proceeds with the “Resistance
Measurement Test” “Driver Bag Low” terminal “4” is
grounded through a current sink and the driver current
source connected to “Driver Bag High” terminal “3” allows
a known amount of current to flow.  By monitoring the
voltage difference between “Driver Bag High” and “Driver
Bag Low” the SDM calculates the combined resistance of
the driver air bag assembly, SRS coil assembly, harness
wiring IB05–YEL and IB06–YEL/BLK and connector
terminal contact.

DTC Will Set When:

The combined resistance of the driver air bag assembly,
SRS Coil assembly, harness wiring IB05–YEL and
IB06–YEL/BLK and connector terminal contact is above a
specified value.  This test is run once each ignition cycle
during the “Resistance Measurement Test” when:

1. No “higher priority faults” are detected during

“Turn–ON” 

2. “Ignition 1” voltage is in the specified value.

Action Taken:

SDM turns “ON” the “AIR BAG” warning lamp and sets
DTC 22.

DTC Will Clear When:

The ignition switch is turned “OFF.”

DTC Chart Test Description:

Number(s) below refer to circled number(s) on the
diagnostic chart:
2. This test determines whether the malfunction is in

the SDM.

3. This test verifies proper connection of the yellow

2–pin connector at the base of the steering column.

4. This test checks for proper operation of the shorting

clip in the yellow 2–pin connector. 

5. This test isolate the malfunction to one side of the

SRS coil assembly yellow 2–pin connector located
at the base of steering column.

6. This test determines whether the malfunction is due

to shortening in the wiring.

7. This test determines whether the malfunction is in

the SRS coil assembly or the driver air bag
assembly.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short
between IB05–YEL or IB06–YEL/BLK or a