SPN 740 - FMI 5 (Diagnostic Code: Transmission Lockup Clutch Solenoid - Current Below Normal)

MID 027 CID 0709 FMI 05 (709-5)

Figure 1.1 - Transm. Lockup Solenoid (244-3114)

Fracturing Transmission TH55-E70

System Response (Symptom)

This Diagnostic Code is associated with the Lockup Clutch Solenoid Valve. The FMI 05 means that the ECM has determined that an open in the circuit exists.

#The possible causes of this Diagnostic Code are listed below: →The energize circuit of the solenoid is open. →The return circuit of the solenoid is open. →The solenoid has failed. →The ECM has failed. This is unlikely.

Note: The following test procedure may create other Diagnostic Codes. Ignore these created Diagnostic Codes and clear these Diagnostic Codes when the original Diagnostic Code has been corrected. Ensure that the Diagnostic Code of CID 0709 FMI 05 is active, before performing this procedure. Use a Digital Multimeter for the measurements in this procedure.

Figure 1.2 - Current Below Normal (709-5)

Test Step 1. CHECK THE SOLENOID

A. Turn the disconnect switch and the key start switch to the ON position. Do not start the Engine. B. Disconnect the solenoid with the active Diagnostic Code from the machine harness.

C. At the machine harness connector for the solenoid, place a jumper wire from contact 1 (wire 756-WH/White) to contact 2 (wire H801-PU/Purple).

D. Observe the status of the CID 0709 FMI 05.

Figure 1.3 - Transm. Lockup Clutch Solenoid (Jumper)

Expected Result: The Diagnostic Code is active. Then, the Diagnostic Code changes from FMI "05" to FMI "06" as the jumper wire is installed.

Results: →YES - The Diagnostic Code remains active. The jumper wire does not affect the Diagnostic Code. Proceed to Test Step 2. →NO - The Diagnostic is no longer active. The solenoid has failed.

Repair: The solenoid has failed. Replace the solenoid (Resistance, around 10 ohms). Verify that the new solenoid corrects the problem (Refer to Figure 1.1).

Figure 1.4 - Lockup Solenoid Short to Ground (709-6)

Test Step 2. CHECK THE HARNESS FOR AN OPEN

A. Turn the key start switch and the disconnect switch to the OFF position.

B. Disconnect the machine harness connector(s) from the ECM.

C. The jumper wire that was installed in the previous Test Step remains in place (Refer to Figure 1.3).

D. At the machine harness connector, measure the resistance from signal contact J1-62 (wire 756 WH/White) to contact J1-60 (wire H801-PU/Purple).

Figure 1.5 - Connections of the Lockup Clutch Solenoid

Expected Result: The resistance is less than 5.0 ohms.

Results: 

→OK - The resistance is less than 5.0 ohms. The machine harness is correct. Proceed to Test Step 3.

→NOT OK - The resistance is greater than 5000 ohms. The resistance measurement is not correct. There is an open circuit in the machine harness.

Repair: Repair the machine harness or replace the machine harness.

Test Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS

A. Inspect the harness connectors. Clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, battery acid, or chafing.

B. Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.

C. Reconnect all harness connectors in order to make sure that the connectors are fully seated. Also, make sure that the clips for each connector are completely fastened.

D. Turn the disconnect switch and the key start switch to the ON position.

E. Operate the machine.

F. Check the status of the CID 0709 FMI 05.

Expected Result: The CID 0709 FMI 05 is active.

Results:

→YES - The CID 0709 FMI 05 is active. The Diagnostic Code has not been corrected.

Repair: Check the circuit again. If the Caterpillar Electronic Technician (Cat ET) is available, use the Cat ET service tool in order to perform a "Wiggle Test" on the machine wiring harness. Read More: Wiggle Test on Caterpillar ET Software. The "Wiggle Test" can detect shorts and opens in the machine wiring harness that are momentary or intermittent. It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the cause of the Diagnostic Code is not found, replace the ECM.

Figure 1.6 - Transm. Lockup Clutch Solenoid (Replaced)

Read More:

SPN 1675 - FMI 5 (Diagnostic Code: Starter Motor Relay - Current Below Normal)

SPN 190 - FMI 2 (Diagnostic Code: Engine Speed Sensor - Erratic, Intermittent, or Incorrect)

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