Reviewers Note: Words/phrases in blue will be links to specific diagnostic procedures when this document is published in Freshdesk.

Blue iQ™ Fault Code List

DSM.0131 Ver. 2.0 June 20, 2023
Click on fault code (FC) number to link to the corresponding diagnostic procedure.
FC

Title

Description

5572

Engine Gaseous Fuel Pressure Regulator Intake
Pressure – Data Valid But Above Normal Operating
Range – Moderately Severe Level

pressure / temperature transducer pressure
above 4500 psi (31 MPa) for more than 2.5
seconds

6845

Engine Gaseous Fuel Temperature Regulator Intake
Temperature Sensor Circuit –
Voltage Below Normal or Shorted to Low Source

pressure / temperature transducer
temperature circuit shorted to ground or
open circuit for more than 0.5 seconds

6849

Gaseous Fuel High Pressure Shutoff Valve –
Current Below Normal or Open Circuit

6857

Fuel System Control Module –
Data Erratic, Intermittent, or Incorrect

common interface fault – information only to
engine. Indicates that data from engine is
not received at normal update rate.

6858

Fuel System Control Module –
Abnormal Update Rate

common interface fault – information only to
engine. Indicates that data from engine is
not received at normal update rate.

6947

Fuel Tank Receptacle Cover –
Mechanical System Not Responding or Out of
Adjustment

receptacle cover open at time of crank
request, crank prevented

6955

Fuel Tank Receptacle Cover Detached During
Operation –
Condition Exists

receptacle cover open during vehicle
operation

6958

Gaseous Fuel High Pressure Shutoff Valve Circuit –
Current Above Normal or Grounded Circuit

solenoid power shorted to ground (more
than 4 A current flow)

6963

Fuel Storage Compartment 1 Temperature – Data
Valid But Above Normal Operating Range –
Most Severe Level

single thermistor above 82.2°C (180°F)

7194

Fuel System Control Module – Data Valid But Below
Normal Operating Range –
Least Severe Level

Engine Inlet Pressure drops below 30 psi
(0.21 MPa) after engine crank start, crank
aborted

7195

Fuel System Control Module – Data Valid But Below
Normal Operating Range –
Moderately Severe Level

Engine Inlet Pressure below 60 psi (0.41
MPa) at time of crank request, crank
prevented

7264

Gaseous Fuel High Pressure Shutoff Valve – Data
Valid But Above Normal Operating Range –
Moderately Severe Level

solenoid power is open circuit
(less than 0.3 A current flow)

supply solenoid valve (SSV) coil resistance
greater than normal

FC

7281

Title

Fuel System Control Module –
Condition Exists

Description

common interface fault – information only to
engine. Indicates there is a fault in the
Hexagon® Agility® system that may cause
an engine performance issue.
NOTE: FC 7281 is secondary to other fault
codes; troubleshoot any other faults first.
12V supply solenoid valve (SSV):
resistance is below 5 ohms for more than
0.4 seconds

7265

Gaseous Fuel High Pressure Shutoff Valve – Data
Valid But Below Normal Operating Range –
Moderately Severe Level

7289

Engine Gaseous Fuel Pressure Regulator Intake
Pressure Circuit –
Voltage Below Normal or Shorted to Low Source

7291

Fuel Storage Compartment 1 Temperature – Data
Valid But Below Normal Operating Range –
Most Severe Level

7292

Fuel Storage Compartment 1 Temperature 1 Sensor
Circuit –
Voltage Above Normal or Shorted to High Source

thermistor 1 circuit shorted to high source or
open circuit

7293

Fuel Storage Compartment 1 Temperature 1 Sensor
Circuit –
Voltage Below Normal or Shorted to Low Source

thermistor 1 circuit shorted to ground

7294

Fuel Storage Compartment 1 Temperature 2 Sensor
Circuit –
Voltage Above Normal or Shorted to High Source

thermistor 2 circuit shorted to high source or
open circuit

7295

Fuel Storage Compartment 1 Temperature 2 Sensor
Circuit –
Voltage Below Normal or Shorted to Low Source

thermistor 2 circuit shorted to ground

7296

Engine Gaseous Fuel Pressure Regulator Intake
Pressure –
Data Valid But Below Normal Operating Range –
Most Severe Level

pressure/temperature transducer pressure
below 250 psi (1.72 MPa) for more than 2.5
seconds

7298

Engine Gaseous Fuel Pressure Regulator Intake
Pressure Circuit –
Voltage Below Normal or Shorted to High Source

pressure/temperature transducer pressure
circuit shorted to high source for more than
0.5 seconds

7299

Engine Gaseous Fuel Temperature Regulator Intake
Temperature – Data Valid But Above Normal
Operating Range –
Moderately Severe Level

pressure/temperature transducer
temperature above 95°C (203°F) for more
than 2.5 seconds

7311

Engine Gaseous Fuel Temperature Regulator Intake
Temperature Sensor Circuit –
Voltage Above Normal or Shorted to High Source

pressure/temperature transducer
temperature circuit shorted to high source
for more than 0.5 seconds

8136

Engine Gaseous Fuel Pressure Regulator Intake
Pressure - Data Valid But Below Normal Operating
Range - Least Severe Level

engine system detected the inlet fuel
pressure dropped below normal operating
range

24V supply solenoid valve (SSV):
resistance is below 15 ohms for more than
0.4 seconds
pressure/temperature transducer pressure
circuit shorted to ground or open for more
than 0.5 seconds
average thermistor temperature below
-45°C (-49°F)

Trademark Notice

Hexagon® is a registered trademark of Hexagon Technology AS. Agility® is a registered trademark of Agility Fuel Solutions LLC. Blue iQ™
is a trademark of Agility Fuel Systems LLC. Trademarks of other manufacturers are the property of their respective companies.