Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 1708

9J1–43

RESTRAINT CONTROL SYSTEM

DTC 25 Driver Deployment Loop Short To Ignition

CAUTION: When Diagnostic Trouble Code (DTC) 25
has been set, it is necessary to replace the Sensing
and Diagnostic Module (SDM). Setting DTC 25  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 given

in the scan tool operator’s manual.

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

Is driver sense low more than 3.5 volts?

Go to 

Step 3

Go to 

Chart A

3

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

base of the steering column. Leave passenger air bag
assembly connected.
Connect SRS driver / passenger load tool J–41433 and
appropriate adapter to SRS coil assembly harness connector.

3. Ignition switch “ON.”

Is driver sense low more than 3.5 volts?

Go to 

Step 4

Go to 

Step 6

4

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

“3” to terminal “12” (Ignition 1).

Does DVM display “0L” (infinite)?

Go to 

Step 5

Replace SRS

harness.

Go to 

Step 7

5

Measure resistance on SDM harness connector from terminal “4”
to terminal “12”  (Ignition 1).

Does DVM display “0L” (infinite)?

Go to 

Chart A

Replace SRS

harness.

Go to 

Step 7

6

1. Ignition switch “OFF.”
2. Connect SRS driver / passenger load tool J–41433 and

appropriate adapter J–35616–A to driver air bag assembly
harness connector located of top of the steering column.

3. Reconnect SRS coil assembly harness connector at the base

of the steering column.

4. Ignition switch “ON.”

Is driver sense low more than 3.5 volts?

Ignition switch

“OFF.”

Replace SRS coil

assembly.

Go to 

Step 7

Ignition switch

“OFF.”

Replace driver air

bag assembly.

Go to 

Step 7

7

1. Reconnect all components, ensure all components are

properly mounted.

2. Ignition switch “ON.”

Is passenger sense low less than 3.5 volts?

Replace SDM.

Go to 

Step 8

Go to 

Chart A

8

1. Reconnect all components, ensure all components 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

9J1–44

DTC 26  Driver Deployment Loop Open

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.
During “Continuous Monitoring” diagnostics, a fixed
amount of current is flowing in the  deployment loop.  This
produces proportional voltage drops in the loop.  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 voltage difference between “Driver Bag High”
terminal “3” and “Driver Bag Low” terminal  “4” is above or
equal to a specified value for 500 milliseconds during
“Continuous  Monitoring.”

Action Taken:

SDM turns “ON” the “AIR BAG” warning lamp and sets a
diagnostic trouble code.

DTC Will Clear When:

The voltage difference between “Driver Bag High”
terminal “3” and “Driver Bag Low” terminal  “4” is below a
specified value for 500 milliseconds during “Continuous
Monitoring.”

9J1–45

RESTRAINT CONTROL SYSTEM

DTC Chart Test Description:

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

the Sensing and Diagnostic Module (SDM).

2. This test verifies proper connection of the yellow

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

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

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

4. This test isolates the malfunction to one side of the

Supplemental Restraint System (SRS) coil
assembly yellow 2–pin connector located at the
base of steering column.

5. This test determines whether the open is in the

wiring.

6. 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 the driver air bag  assembly harness 2–pin
connector terminals “1” and “2” at the top of the steering
column,  SRS coil assembly harness 2–pin connection
terminals “1” and “2”, SDM terminals “3”  and “4”, or an
open in Circuits(CKTs) IB05–YELLOW and
IB06–YELLOW/BLACK.

RESTRAINT CONTROL SYSTEM

9J1–46

DTC 26 Driver Deployment Loop Open

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

differential voltage.

Is driver differential voltage more than 4.25 volts?

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 yellow 2–pin connector connected properly?

Go to 

Step 4

Seat driver air

bag assembly

2–pin connector.

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 26 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 26 current?

Go to 

Step 6

Go to 

Step 7

6

1. Ignition switch “OFF.”
2. There has been an open circuit in the driver deployment loop.

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 on steering

column.

4. Reconnect SRS coil assembly harness connector as the base

of steering column.

5. Ignition switch “ON.”

Is DTC 26 current?

Ignition switch

“OFF.”

Replace SRS coil

assembly, refer to

in this section.

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