Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1705

9J1–31

RESTRAINT CONTROL SYSTEM

DTC 19 Passenger Deployment Loop Short To Voltage

D09R100002

Circuit Description:

When the ignition switch is turned “ON”, the Sensing and
Diagnostic Module (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 monitors the voltages at “Driver Bag Low”
terminal “4” and “Passenger Bag Low”  terminal “16” to
detect short to B+ in the air bag assembly circuits.

DTC Will Set When:

“Ignition 1” is within the normal operating voltage range.
Once these conditions are met  and the voltage at
“Passenger Bag Low” is above a specified value,
Diagnostic Trouble Code (DTC) 19 will set.  This  test is
run once each ignition cycle and “Continuous Monitoring”.

Action Taken:

SDM turns “ON” the “AIR BAG” warning lamp and sets
DTC 19 and also DTC 71.

DTC Will Clear When:

The SDM is replaced.

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 isolates the malfunction to one side of the

passenger air bag assembly yellow  2–pin connector
behind glove box compartment.

4. This test determines whether the malfunction is in

Circuit(CKT) IB07–YELLOW/GREEN.

RESTRAINT CONTROL SYSTEM

9J1–32

5. This test determines whether the malfunction is in

CKT IB08–YELLOW/RED.

Diagnostic Aids:

An intermittent condition is likely to be caused by a short
to B+ in the passenger air bag  assembly circuit.   Inspect
CKTs IB07–YELLOW/GREEN and IB08–YELLOW/RED

carefully for cutting or chafing.   If the wiring pigtail of the
passenger air bag assembly is damaged, the component
must be  replaced.   A careful inspection of CKT
IB07–YELLOW/GREEN and IB08–YELLOW/RED,
including the  passenger air bag assembly pigtail is
essential to ensure that the replacement Sensing and
Diagnostic Module (SDM) will not  be damaged.

DTC 19 Passenger Deployment Loop Short To Voltage

CAUTION: When DTC 19 has been set, it is
necessary to replace the Sensing and Diagnostic
Module (SDM).  Setting Diagnostic Trouble Code
(DTC) 19  and 25 or 51 or 53 will also cause DTC 71
to set.  When a scan tool “CLEAR CODES” command

is issued and  the malfunction is no longer present,
DTC 71 will remain current.  Ensure that the short  to
voltage condition is repaired prior to installing a
replacement SDM to avoid damaging the SDM.

Step

Action

Yes

No

1

Was the “SRS Diagnostic System Check” performed?

Go to 

Step 2

Go to 

“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. Ignition switch “OFF.”
3. Connect scan tool data link connector.  Follow directions as

given in the scan tool operator’s manual.

4. Ignition switch “ON.”
5. Read passenger sense low.

Is passenger sense low more than 3.5 volts?

Go to 

Step 3

Go to 

Chart A

3

1. Ignition switch “OFF.”
2. Disconnect passenger air bag assembly yellow 2–pin

connector behind the glove box assembly.

3. Leave driver air bag assembly connected.
4. Connect SRS driver / passenger load tool J–41433 and

appropriate adapter to  passenger air bag assembly harness
connector.

5. Ignition switch “ON.”

Is passenger sense low more than 3.5 volts?

Go to 

Step 4

Ignition switch

“OFF.”

Replace

passenger air

bag assembly.

Go to 

Step 6

4

1. Ignition switch “OFF.”
2. Disconnect SDM.
3. Disconnect SRS driver / passenger load tool.
4. Measure resistance on SDM harness connector from terminal

“15” to terminal “12” (IGNITION 1).

Does DVM display “0L” (infinite)?

Go to 

Step 5

Replace SRS

harness.

Go to 

Step 6

5

Measure resistance on SDM harness connector from terminal
“16” to terminal “12” (IGNITION 1).

Does DVM display “0L” (infinite)?

Go to 

Chart A

Replace SRS

harness.

Go to 

Step 6

6

1. Reconnect all components, ensure all component are properly

mounted.

2. Ignition switch “ON.”

Is passenger sense low less than 3.5 volts?

Ignition switch

“OFF.”Replace

SDM.Go to 

Step

7

Go to 

Chart A

7

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 7

9J1–33

RESTRAINT CONTROL SYSTEM

DTC 21  Driver Deployment Loop Resistance High

D09R100002

Circuit Description:

When the ignition switch is turned “ON”, the Sensing and
Diagnostic Module (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 Circuits(CKTs) IB05–YELLOW and
IB06–YELLOW/BLACK, and connector terminal contact.

DTC Will Set When:

The combined resistance of the driver air bag assembly,
SRS Coil assembly, harness wiring  CKTs
IB05–YELLOW and IB06–YELLOW/BLACK, and
connector terminal contact is above a  specified value.
This test run once each ignition cycle during the
“Resistance Measurement  Test” when:
No “higher priority faults” are detected during

“Turn–ON”

“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”.

RESTRAINT CONTROL SYSTEM

9J1–34

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 Sensing and Diagnostic Module (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

Supplemental Restraint System (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.

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 Circuit
IB05–YELLOW or  IB06–YELLOW/BLACK.  The test for
this diagnostic trouble code is only run while the “AIR
BAG” warning lamp is performing the bulb check, unless
Diagnostic Trouble Code (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.