Electronic Control System Signature, ISX and QSX15 Engines – FAULT CODE 469

ICON™ Cab Thermostat Circuit


Fault Code: 469
PID: S215
SPN: 614
FMI: 2/2
LAMP: Yellow

The ICON™ cab thermostat has logged a fault (displayed on thermostat as E3) or cab thermostat signal to the electronic control module (ECM) is lost.

E3 will cycle the engine between 20 minutes RUN and 15 minutes OFF, or will not autostart the engine for Cab Comfort mode. ICON™ will not be disabled. Engine mode will remain active.

ICON™ Cab Thermostat Circuit

Circuit Description

The cab thermostat is used to control the cab temperature for either heating or cooling. It is required for Cab Comfort mode operation. The thermostat communicates with the ECM to command when to autostart the engine to maintain cab temperature. The thermostat is also connected to the keyswitch to detect when the ignition is turned on.

Component Location

The cab thermostat is typically mounted in the bunk area, above the bed on the wall. Use the specific, appropriate OEM manual for the exact location.

Shop Talk

E3 is an indication that one of the following has occurred:

Engine has run for more than 45 minutes and the ambient temperature is within 0 to 100°F (thermostat-adjustable trim 01 and 02) or a cab thermostat request to start the engine has been made within 10 minutes of an automatic shutdown and the ambient temperature is within 0 to 100°F. E3 can indicate potential tampering with the thermostat. For example, in the summer (78°F ambient) the user can set the thermostat to Heat mode with a set point of 75°F, but set the truck climate controls to Maximum Cooling.

The truck will only cool to some temperature below 75°F and run for 45 minutes before logging the E3. The effect of an E3 fault is adjustable via the thermostat between cycle engine on for 20 minutes and off for 15 minutes, or will not perform an autostart.

Refer to Troubleshooting Fault Code t05-469.

Last Modified:  26-Oct-2010