Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 520

9J1–27

RESTRAINT CONTROL SYSTEM

DTC 21 Driver Deployment Loop Resistance High 

Step

Action

Yes

No

1

Was the “SRS Diagnostic System Check”  performed?

Go to 

Step 2 

Go to the “SRS

Diagnostic

System Check.”

2

1. When measurements are requested in this chart use J–39200

DVM with correct terminal adapter from J–35616–A.

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

deployment loop resistance.

Is driver deployment loop resistance more than 4.4 ohms?

Go to 

Step 3 

Go to 

Chart A .

3

1. Ignition switch “OFF.”
2. Disconnect driver air bag 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 

Ignition switch

“OFF.”

Go to 

Step 8 

5

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

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

3. Connect SRS driver / passenger load tool J–41433 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 CKTs IB05–YEL/IB06–GRN and 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 .

7

1. Ignition switch “OFF.”

Disconnect SRS driver / passenger load tool from SRS coil
assembly harness connector.
Connect SRS driver / passenger load tool J–41433 on the top
of steering column.
Reconnect SRS coil assembly harness connector as the base
of steering column.
Ignition switch “ON.”

Is DTC 21 current?

Ignition switch

“OFF.”

Replace SRS

COIL

ASSEMBLY.

Refer to in this
section 9J–24.

Go to 

Step 8 

Ignition switch

“OFF.”

Replace driver air

bag assembly.

Go to 

Step 8 

8

Reconnect all components, ensure all component are properly
mounted.

Clear diagnostic trouble codes.

Was this step finished?

Repeat the “SRS

Diagnostic

System Check.” 

Go to 

Step 8 .

RESTRAINT CONTROL SYSTEM

9J1–28

DTC 22  Driver Deployment Loop Resistance Low

D09R200001

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 CKTs
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 CKTs 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.”

9J1–29

RESTRAINT CONTROL SYSTEM

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 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 shorting 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 CKT IB05–YEL or IB06–YEL/BLK or a
malfunctioning shorting clip on the driver air bag
assembly or SRS coil assembly which would require
replacement of the component.  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.

RESTRAINT CONTROL SYSTEM

9J1–30

DTC 22 Driver Deployment Loop Resistance Low 

Step

Action

Yes

No

1

Was the “SRS Diagnostic System Check” performed?

Go to 

Step 2 

Go to the “SRS

Diagnostic

System Check.”

2

1. When measurements are requested in this chart use J–39200

DVM with correct terminal adapter from J–35616–A.

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

deployment loop resistance.

Is driver resist. less than 1.9 ohms?

Go to 

Step 3 

Go to 

Chart A .

3

1. Ignition switch “OFF.”
2. Make sure the SRS coil assembly yellow 2–pin connector

located at the base of steering column is seated properly.

Is the 2–pin connector connected properly?

Go to 

Step 4 

Seat driver air

bag 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 driver air bag assembly yellow 2–pin

connector.

3. Ignition switch “ON.”

Is DTC 22 current?

Go to 

Step 5 

Ignition switch

“OFF.”

Go to 

Step 8 

5

1. Ignition switch “OFF.”
2. Disconnect SRS coil and passenger air bag 2–pin connectors

located at the base of steering column and behind the glove
box assembly.

3. Connect SRS driver / passenger load tool J–41433 and

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

4. Ignition switch “ON.”

Is DTC 22 current?

Go to 

Step 6 

Go to 

Step 7 

6

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

driver deployment loop.

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

checking CKTs 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 .

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 J–41433 to the top

of steering column.

4. Reconnect SRS coil assembly harness connector as the base

of steering column.

5. Ignition switch “ON.”

Is DTC 22 current?

Ignition switch

“OFF.”

Replace SRS coil

assembly.

Refer to in this
section 9J–24.

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