TSB200123-060920

6/18/2020
Dash Lamps Illuminated Always after CM2380 ECM Upfit
Technical Service Bulletin
Technical Service Bulletin: TSB200123
Released Date: 09-Jun-2020
Dash Lamps Illuminated Always after CM2380 ECM Upfit
Dash Lamps Illuminated Always after CM2380 ECM
Upfit
Warranty Statement
The information in this document has no effect on present warranty coverage or repair practices,
nor does it authorize TRP or Campaign actions.
Contents
Product Affected
ISL G CM2180
ISX12 G CM2180 EJ
Issue
Symptom:
Check Engine Lamp, Stop Engine Lamp, Malfunction Indicator Lamp, and Low Fuel Pressure
Lamp are illuminated always after upfitting the engine to a CM2380 ECM.
Root Cause:
Changes in the CM2380 ECM lamp driver circuits are not compatible with 24 VDC dash lamp
circuits. This change results in the ECM driven lamps being illuminated always.
Verification
Check for 24 VDC at the OEM harness 31 pin connector on pins 1, 2, 4, and 25. If 24 VDC is
present the lamp circuit will not function properly with a CM2380 ECM.
Resolution
Contact the OEM to see if the dash lamps can be converted to 12 VDC. If conversion of dash
lamps to 12 VDC is not feasible a standard 12 VDC normally open automotive relay can be used
to restore functionality of the dash lamps. An individual relay will be needed for each dash lamp.
Reason for Change
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Dash Lamps Illuminated Always after CM2380 ECM Upfit
12 VDC dash lamps were required per engine installation instructions. However, some OEM
installations utilized 24 VDC dash lamps. With CM2180 ECMs the dash lamps still functioned as
intended with the higher voltages.
Service Instructions
If possible, work with the OEM to update the dash lamps to 12 VDC. In some instances, this
update might not be feasible. If the OEM is not able to update the dash, a standard 12 VDC
automotive relay must be used to restore dash lamp functionality. Two example circuits are shown
in Figure 1 and Figure 2 below. An individual relay will be needed for each dash lamp.
Figure 1, Relay Wiring Example Circuit
Figure 1 Pin Connections:
Pin 86: 12 VDC Switched Power
Pin 85: OEM 31 Pin Connector Lamp Signal Circuit
Pin 87: OEM 31 Pin Chassis Ground
Pin 87A: Not Used
Pin 30: Lamp Signal Circuit from the OEM Dash
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Dash Lamps Illuminated Always after CM2380 ECM Upfit
Figure 2, Relay Wiring Example Circuit
Figure 2 Pin Connections:
Pin 86: 12 VDC Switched Power
Pin 85: OEM 31 Pin Connector Lamp Signal Circuit
Pin 87: OEM 31 Pin Connector Lamp Signal Circuit
Pin 87A: Not Used
Pin 30: Lamp Signal Circuit from the OEM Dash
Document History
Date
2020-6-1
Details
Module Created
Last Modified: 09-Jun-2020
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