Electrical 389 Family
Peterbilt Motors Company 6-3
ESA IDENTIFICATION
Connecting using ESA 2.0 brings up a control module information window. In this window, the fourth line item is the
Control Unit Type and identifies whether the truck has an ICU or CECU.
FIGURE 6-2. ESA Identification, Programming Date and Module Software Version
DOME LIGHT IDENTIFICATION
The CECU system has an updated feature that delays turning the dome light off when you close the door. The previous
ICU system did not have this function so the light turns off as soon as the door is shut. Therefore, if the dome light does
not turn off immediately after all doors are shut, then the vehicle has a CECU system. If the dome light does turn off
immediately, then the vehicle may be ICU OR CECU with this function disabled. In these cases, you will need to refer to
ECAT for verification.
Comparison Chart
The following charts show the differences between the ICU and CECU.
The first chart provides an alphabetical listing of the features available for either an ICU or CECU. Since the CECU is an
updated ICU, almost all of the features of an ICU are found in a CECU, except a few out dated options such as the
pyrometer.
The similarity of the modules is easily seen in the second chart as well. This chart is an abbreviated connector pinout of
each module. Since the same wiring connections are used for both modules, it’s easy to see that the CECU has more
circuits to handle the increase in multiplexed features.
