TSB1900030108201

CM2350 Engine Control Module (ECM) Malfunctions Due to Incorrect Switch Input Wir... Page 1 of 3
Technical Service Bulletin
Technical Service Bulletin:
Released Date: 08-Jan-2019
TSB190003
CM2350 Engine Control Module (ECM) Malfunctions Due to Incorrect Switch
Input Wiring
CM2350 Engine Control Module (ECM)
Malfunctions Due to Incorrect Switch Input
Wiring
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
•
•
•
•
•
•
•
•
•
B6.7 CM2350 B121B
B6.7 CM2350 B135B
B6.7 CM2350 B148B
L9 CM2350 L116B
L9 CM2350 L119B
L9 CM2350 L123B
X12 CM2350 X119B
X15 CM2350 X114B
X15 CM2350 X116B
Issue
Symptom:
• Engine control module (ECM) switch inputs, such as the power take-off
(PTO)/Accelerator Interlock/Oil pressure switch, are inoperable.
• Fault Codes 175, 176, and 415 (B6.7 Only).
• Fault Codes 5879 and 5881 (B, L9, X12 and X15 2017 engines).
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CM2350 Engine Control Module (ECM) Malfunctions Due to Incorrect Switch Input Wir... Page 2 of 3
Root Cause:
• ECM switch inputs are wired incorrectly.
Confirmation
Perform the following steps to check and verify that the ECM switch inputs are wired
correctly.
1. Remove the original equipment manufacturer (OEM) connector from the ECM.
2. Use a multimeter to measure for voltage between pins 11, 12, 19, 20, 43, 44, 47, 66
through 70, 86 through 94, and ECM switch RETURN pin 62 at the OEM harness
connector.
◦ Specific pins used in the connector depend on what switches were installed by
the OEM.
3. Toggle the switch to ground inputs and check for battery voltage with the keyswitch
in both the ON and OFF positions.
Multimeter must show 0.0 volts. If any voltage is observed, the switch must be wired
correctly before the ECM is installed.
Reference the circuit diagram or wiring diagram for connector pin identification.
Use the following procedure for general multimeter usage techniques.
The resistance measurement given in this document of 0.020 Ohms is different than the
Service Manual specification.
Perform the following steps to check and verify that the ECM power return (ground) wires
are grounded correctly.
1. Disconnect the batteries. See equipment manufacturer service information.
2. Use a multimeter to measure the resistance between the OEM connector ECM
ground return pins and Battery (-) cable connection.
3. The multimeter ohm reading must be less than 0.020 Ohms. If reading is not less
than 0.020 Ohms, the high resistance ground connection must be corrected.
4. Reconnect batteries. See equipment manufacturer service information.
5. With all components connected, use a multimeter to measure the voltage between
the engine ECM block ground stud and battery negative connection with the
following conditions met in order:
◦ Key off
◦ Key on; engine not running
◦ Key on; engine running and electrical accessories on
6. The multimeter must show less than 0.5VDC. If voltage is not less than 0.5VDC, the
high resistance ground connection must be corrected.
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CM2350 Engine Control Module (ECM) Malfunctions Due to Incorrect Switch Input Wir... Page 3 of 3
Reference the circuit diagram or wiring diagram for connector pin identification.
Use the following procedure for general multimeter usage techniques. See the
corresponding Service Manual. Reference Procedure 019-359 in Section 19.
Resolution
If any of the pins show a voltage with the multimeter when the switches are toggled, the
switch must be wired correctly, so an open or ground is observed. If the ECM is installed
before the switch is wired correctly, the ECM will be susceptible to repeat malfunctions.
Subsequent damage to the ECM, caused by incorrectly wiring wired switches prior to
ECM installation, will not be warrantable.
ECM power return (ground) wiring must be connected to the engine cylinder block
ground stud and then return from the engine cylinder block to the battery by a low
resistance circuit of 0.020 Ohms or less between the ECM and battery.
Sustained voltage differential or peak-peak voltage differential levels between the engine
ECM cylinder block ground stud and battery negative not to exceed 0.5VDC.
Document History
Date
2019-1-8
Details
Module Created
Last Modified: 08-Jan-2019
https://quickserve.cummins.com/qs3/pubsys2/xml/en/tsb/2019/tsb190003.html
1/28/2019