Blue iQ® Fault Codes
7292 & 7293

Diagnostic Procedure
FC

SPN

FMI

Description

7292 8420

3

Fuel Storage Compartment 1 Temperature - Voltage below normal or shorted to a low source
- Most Severe Level

7293 8420

4

Fuel Storage Compartment 1 Temperature - Voltage above normal or shorted to a high
source - Most Severe Level

Part(s) Affected

Thermistor 1 – called “Fuel Storage Compartment Temperature Sensor 1” in Cummins INSITE™

Diagnostic Overview
The Blue iQ® Fuel System Control Module (FSCM) monitors fuel storage compartment(s) internal temperature
by checking two temperature sensors (called “thermistors” by Hexagon Agility®) for any abnormal temperature
values. When the FSCM detects sensor voltage below normal, above normal, or shorted on one or more
of the temperature sensors, it sets a fault code. In some cases, the FSCM also may send a signal to the Blue
iQ gauge causing the indicator LED to blink red and the gauge display to show a fuel system over temperature
warning.

Warning Statements Used in this Procedure
NOTICE is used to address practices not related to physical injury, such as best practices
or tips to help an operation or procedure go smoothly and prevent equipment damage.

Tools Required
Item

Purpose

digital multimeter (DMM)

resistance and voltage measurements

J1939 OBD-II diagnostic interface

connect vehicle to Cummins® INSITE™ on PC

Cummins® INSITE™

diagnostic software

test lead kit

properly test and back probe circuit terminals and connectors

infrared non-contact thermometer

accurately measure SSV coil temperature

Never probe an electrical connection with anything other than a properly sized
and shaped test lead; doing so may result in damage to terminals.

Circuit / Sensor Description
Thermistor 1 has a 5V Signal circuit and a Low Reference circuit which are provided from the FSCM. The signal
circuit in the FSCM monitors the 5V reference using a pull-up resistor; if there is an open circuit, the analog pin
will default to the peak 5V reading.
The Thermistor 1 Low Reference circuit is shared with Thermistor 2.
Refer to Thermistor Circuit Diagram (below) for wiring details.
Refer to Thermistors section of DSM.0001 for component locations in various fuel system configurations.

DSM.0029 Ver 1.0
July 15, 2021

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

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Diagnostic Aids
During normal operation, the temperature inside the fuel system cabinet should not exceed 165°F (73.8°C); if
the temperature exceeds this value a Fuel System Over Temp warning screen on the Blue iQ® gauge will notify
the operator.
Perform Initial Vehicle Check procedure (refer to DSM.0009) prior to performing
diagnostic instructions listed below.

Circuit / System Verification
1. Connect diagnostic tool to the vehicle and navigate to the “Agility® Fuel Delivery System, CM1881
AFS(18)” in Cummins® INSITE™.
2. Record all active and stored fault codes and parameters prior to clearing fault codes using INSITE™.
3. Observe and record Fuel Storage Compartment Temperature Sensor 1 data from INSITE™—is data
within reasonable operating range?
a. If not within range proceed to Circuit/System Testing.
b. If within range proceed to Step 4.
4. Operate the vehicle in the same conditions for enabling the fault code or within the same conditions that
triggered the fault code based on recorded data.
5. Verify that the fault code does not set. If any fault code sets proceed to Circuit/System Testing.
6. While observing Fuel Storage Compartment Temperature Sensor 1 parameters in INSITE™ perform
a wiggle test on the FSCM and Thermistor 1 connectors and harness to test for poor or intermittent
connections.
a. If any fault code sets, proceed to Circuit/System Testing.
b. If no fault code sets, system is functioning to design intent.
7. Review Circuit Schematic and Connector End Views to locate test points (refer to DSM.0001).

DSM.0029 Ver 1.0
July 15, 2021

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

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Thermistor 1 & 2 (Fuel Storage Compartment Temperature Sensor #1 & #2) Circuit Diagram

DSM.0029 Ver 1.0
July 15, 2021

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

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Circuit / System Testing
Step
1

 Ignition Off, Engine Off.
 Disconnect Thermistor 1 from Blue iQ chassis harness.
 Use a DMM and appropriate test leads to measure resistance across Terminal A and Terminal B of
Thermistor 1 connector and record the value.

Terminal A

Terminal B

thermistor connector end view
 Use a non-contact infrared thermometer to measure temperature at Thermistor 1; record the value.
According to TABLE 1 below, is the measured resistance value within the specified resistance
range?
TABLE 1.
Thermistor Resistance* vs. Temperature.
Temp
°F
°C
-40
-40
-22
-30
-4
-20
14
-10
32
0
50
10
77
25

86

104
122
140
158
176
194
212

30

40
50
60
70
80
90
100

Resistance Range
(ohms)
32277
to
35177
17083
to
18359
9413
to
10015
5397
to
5673
3197
to
3335
1954
to
2026
989
to
1011

796
524
352
243
170
122
89
66

to
to
to
to
to
to
to
to

816
542
368
255
180
130
95
70

*Resistance must be within tolerance range shown.

Yes
 Proceed to Step 2.

DSM.0029 Ver 1.0
July 15, 2021

No
 Replace Thermistor 1; refer to Thermistor
Replacement Procedure in DSM.0001.
 Proceed to Reassembly and Validation.

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
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Step
2

 Ignition On, Engine On.
 Use a DMM and appropriate test leads to test for 4.8-5.2 V between Thermistor 1 harness connector
5V Signal Cavity A and Low Reference Cavity B.

Cavity B

Cavity A

thermistor harness connector end view
What is the voltage reading?
Less than 4.8 V
 Proceed to Step 3.

Step
3

Between 4.8-5.2 V
 Replace Thermistor 2; refer to
Thermistor Replacement
Procedure in DSM.0001.
 Proceed to Reassembly and
Validation.

Greater than 5.2 V
 Proceed to Step 6.

 Ignition On, Engine On.
 Use a DMM and appropriate test leads to test for 4.8-5.2 V between Thermistor 1 harness connector
5V Signal Cavity A and a known good ground such as the chassis frame rail.

Cavity A

thermistor harness connector end view
Voltage reading between 4.8 V and 5.2 V?
Yes
 Proceed to Step 7.

DSM.0029 Ver 1.0
July 15, 2021

No
 Proceed to Step 4.

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

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Step
4

 Ignition Off.
 Disconnect FSCM Blue iQ harness connector.
 Use a DMM and appropriate test leads to test for infinite resistance between FSCM harness
connector Cavity 13 and a known good ground.
Cavity 13

FSCM connector end view
Infinite resistance?
Yes
 Short to ground; repair 5V Signal circuit.
 Proceed to Reassembly and Validation.
Step
5

No
 Proceed to Step 5.

 Ignition Off.
 Use a DMM and appropriate test leads to test for less than 2 ohms of resistance in the 5V Signal
circuit from FSCM harness connector Cavity 13 to Thermistor 1 harness connector Cavity A.
Cavity 13

Cavity A

FSCM connector end view

thermistor harness connector end view

Resistance between zero and 2 ohms?
Yes
 Circuit is good; FSCM issue indicated.
 Contact Hexagon Agility® Technical
Support.

DSM.0029 Ver 1.0
July 15, 2021

No
 Open circuit or high resistance; repair 5V
Signal circuit.
 Proceed to Reassembly and Validation.

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
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Step
6






Ignition Off.
Disconnect FSCM Blue iQ harness connector.
Ignition On.
Use a DMM and appropriate test leads to test for less than 1 V between the FSCM harness connector
Cavity 13 and known good ground.
Cavity 13

FSCM connector end view
Voltage between zero and 1 volts?
Yes
 Circuit is good; FSCM issue indicated.
 Contact Hexagon Agility® Technical
Support.
Step
7

No
 Short to voltage; repair 5V Signal circuit.
 Proceed to Reassembly and Validation.

 Ignition Off.
 Disconnect FSCM connector.
 Use a DMM and appropriate test leads to test for less than 2 ohms of resistance between FSCM
harness connector Cavity 28 and Thermistor 1 harness connector Cavity B.
Cavity 28

Cavity B

thermistor harness connector end view

FSCM connector end view
Resistance between zero and 2 ohms?
Yes
 Circuit is good; FSCM issue indicated.
 Contact Hexagon Agility® Technical
Support.

DSM.0029 Ver 1.0
July 15, 2021

No

 Open circuit or high resistance; repair Low
Reference circuit.

 Proceed to Reassembly and Validation.

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

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Reassembly and Validation
After completing all repairs, always perform the following steps to confirm the issue is fixed:
1. Reconnect all connectors and verify connections are secure.
2. Reattach any enclosure covers and close any fuel system doors.
3. Clear fault codes using Cummins® INSITE™ tool.
4. Run vehicle until it reaches normal operating temperature. Refer to OEM instructions.
5. If fault is cleared, return vehicle to duty.

6.

If fault is not cleared, contact Hexagon Agility® Technical Support.

Hexagon Agility® Customer Care and Technical Services
Fuel system warranty or non-warranty product support may be obtained by calling or emailing Hexagon Agility® Customer
Care and Technical Services (CCTS).
Please provide your name, phone number, email address, and complete vehicle information: VIN, year, make, model,
mileage, unit number vehicle owner, and current vehicle location. A service advisor will contact you to arrange vehicle
repair or ship a part.

+1 855 500 2445

(toll-free, U.S. and Canada)

+1 949 267 7745

Support
[email protected]

Parts Orders
[email protected]

Proprietary Statement
The information provided within this document is proprietary and confidential. All prior versions, including updates and revisions forwarded separately, are
proprietary. The information provided by Hexagon Agility® to its customers and clients is solely for the use of those customers and clients. No portion of
this publication may be reproduced or distributed without express written consent of Hexagon Agility®. Hexagon Agility® reserves the right to utilize the
intellectual property contained within this publication as content for any other publication produced by Hexagon Agility®.

Trademark Notice
Hexagon® is a registered trademark of Hexagon Technology AS. Agility® is a registered trademark of Agility Fuel Solutions LLC. Trademarks of other
manufacturers are the property of their respective companies.

Hexagon Agility®

DSM.0029 Ver 1.0
July 15, 2021

3335 Susan Street, Suite 100 Costa Mesa, CA 92626 USA

Blue iQ® Fault Code 7292 and 7293 Diagnostic Procedure
PRINTED AND DOWNLOADED COPIES ARE UNCONTROLLED

www.hexagonagility.com

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