The machine is a D6R and the brakes seem to come on in reverse or forward. The service codes are 113, 0668.12, 0689.06,

Hello,

This is not likely to be cause by an electrical problem.

You must have some internal leakage that is causing this issue.

Detailed pressure testing will be needed to isolate the problem.

Here are details about the codes you posted.

CID 0668 - Transmission Shift Lever: FMI 12 Bad device or component.

This code is seen often when the lever sensor is worn but, not damaged. If the code is not active, it should not be a concern.

CID 0689 - Left Steering Brake Solenoid: FMI 06 Current above normal or grounded circuit.

This code can be relate but, it depends on the design of this tractor.

I will need to know the full machine serial number to determine if it is related. However, if this code is active you would never be able to release the brakes.

Please post the full machine serial number and let me know if these codes are active or logged.

Do you have CAT ET, SIS and pressure testing tooling available?

Thank you for the serial number.

Can you please tell me if you have CAT ET?

Do you have access to SIS service information?

Do you know if the codes are active or logged?

Below are details for the brake fault code.

Configuration: D6R Series IIDS,LGP TRACK-TYPE TRACTOR AEP00001-UP (MACHINE) POWERED BY C-9 Engine
MID 113 - CID 0689 - FMI 06
Conditions Which Generate This Code:
This diagnostic code is for the Solenoid for the Left Steering Brake. (Differential steering machines only use one brake solenoid.)
This diagnostic code is recorded when the current of the solenoid circuit is above normal.
Note: Ensure that CID 0689 FMI 06 for the solenoid is on hold and that the diagnostic code indicator shows "SERV CODE".

Test Step 1. CHECK THE SOLENOID.

Turn the key start switch to the ON position.
Ensure that the CID 0689 FMI 06 diagnostic code for the solenoid is on hold.
Observe the status of the diagnostic code indicator.
Disconnect the machine harness from the solenoid.
Expected Result:

"SERV CODE" is not displayed when the solenoid is disconnected.

Results:

YES - "SERV CODE" is not displayed when the solenoid is disconnected.
Repair: The circuit is correct. The solenoid has failed. Repeat this step in order to verify the solenoid failure.

Stop.

NO - "SERV CODE" is displayed when the solenoid is disconnected. The diagnostic code remains. Proceed to Test Step 2.
Test Step 2. CHECK THE SIGNAL CIRCUIT OF THE SOLENOID FOR A SHORT TO GROUND.

Turn the key start switch to the OFF position. The machine harness remains disconnected from the switch.
Disconnect the machine harness from the solenoid.
Disconnect the machine harness connectors J1 and J2 from the ECM.
At machine harness connector J2, measure the resistance from the solenoid signal contact to all possible sources of ground. The possible ground sources are contact J1-2, contact J1-5, contact J1-7, contact J1-15, contact J1-16, contact J2-3, and frame ground.
Expected Result:

Each resistance should be greater than 5000 ohms.

Results:

OK - Each resistance is greater than 5000 ohms. The machine harness is correct. Proceed to Test Step 3.
NOT OK - Each resistance is not greater than 5000 ohms.
Repair: There is a short in the machine harness. The short is between the wire for the solenoid signal and the circuit that has a low resistance measurement. Repair the machine harness or replace the machine harness.

Stop.

Test Step 3. DETERMINE IF THE DIAGNOSTIC CODE IS STILL ACTIVE.

Inspect the contacts and clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the key start switch to the ON position.
Enter service mode of the Caterpillar Monitoring System and clear all inactive diagnostic codes.
Operate the machine.
Stop the machine and place the parking brake switch in the ON position.
Determine if the CID 0689 FMI 06 diagnostic code for the solenoid is present. "SERV CODE" is showing.
Expected Result:

CID 0689 FMI 06 for the solenoid is present. "SERV CODE" is showing.

Results:

YES - CID 0689 FMI 06 for the solenoid is present. "SERV CODE" is showing.
Repair: Exit this procedure and perform the diagnostic code procedure again. If the problem persists, the ECM may have failed. Prior to replacing an ECM, always contact your dealership's Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce repair time. See the Testing and Adjusting, "Electronic Control Module (ECM) - Replace".

Stop.

NO - CID 0689 FMI 06 for the solenoid is not present. "SERV CODE" is not showing.
Repair: The problem does not exist at this time. The initial problem was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.

Stop.

With out the tooling to perform pressure testing, I can only suggest you remove and inspect the priority valve.

This is located at the bottom left side of the transmission case between torque converter and transmission. (You will need to remove the belly pan to access it.)

Replacing the priority solenoid may help too. It is part number(###) ###-#### ***** internal spool could be sticking or not sealing correctly.

Please let me know if you need more help on this problem.

Thanks, Donnie

Here is an image of the valve.

Here is a location view.

They do not look like any codes I have ever seen.

Last codes listed for this model are below 2000. The highs code number CAT uses currently is below 5000.

How are you seeing these codes?

Do you have CAT ET?

Electronic Technician.

It is the service program used by CAT with the ECMs.

???

Where did you get these codes from?

If they were pulled from the dash by using the information button, it could be mileage in forward and reverse.

All fault codes have a MID (module id) for the ECM it came from followed by the CID (component id) of the part and FMI (failure mode id) for the type of failure. Example 113 for transmission, 299 for shift position sensor and F13 for calibration 113 299F13

Ok, Please let me know how the codes are being viewed and list all the codes in the order they scroll past.

Please not the active codes too. (The words SERV CODE will be present with the code when it is active.