C15 – Eaton Top 2 Transmission Circuit – Test

System Operation Description:

Use this procedure under the following situation:
The “Transmission Style” parameter is programmed to Eaton Top 2 and one of the following diagnostic codes is active or easily repeatable:
• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high

• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high
• 191-07 Transmission Not Responding
The following background information is related to this procedure:

Overview Of The Transmission

The engine ECM controls shifts between the top two gears of an Eaton Top 2 transmission. The shift points are based on engine speed and load for added driving ease. When the transmission is in the Top 2 gears, the ECM will perform the following functions:

• Shift the transmission between the top 2 gears automatically.
• Increase or decrease engine speed during a Top 2 shift.
• Momentarily interrupt the cruise control or the engine brake during the shift. Then, the cruise control or the engine brake will resume.

Note: Top gear refers to tenth gear in a ten speed transmission, and top gear refers to thirteenth gear in a thirteen speed transmission. Top gear minus one refers to ninth gear in a ten speed transmission, and top gear minus one refers to twelfth gear in a thirteen speed transmission. Top gear minus two refers to eighth gear in a ten speed transmission, and top gear minus two refers to eleventh gear in a thirteen speed transmission.

Transmission Upshift By The ECM

Upshift the transmission through the shift pattern to top gear minus two. Use double clutching during the lever shifts. Break torque during button shifts.

When the engine has reached the shift point use double clutching and move the shift lever into the Top Gear Minus One position (automatic position).

Note: Leave the shift button in the forward position so that the shift button is ready for downshifting into the Top Gear Minus Two position.

When the engine has reached the upshift point the ECM will automatically shift the transmission into Top Gear. The ECM shifts the transmission into Top Gear by turning on the shift solenoid and turning off the lockout solenoid.

Transmission Downshift By The ECM

Once the engine has reached the shift point, the ECM will automatically downshift the transmission from Top Gear to Top Gear Minus One. The ECM downshifts the transmission from Top Gear to Top Gear Minus One by turning on the lockout solenoid and turning off the shift solenoid.

In order to downshift from Top Gear Minus One to Top Gear Minus Two, make sure that the shift button is in the forward position. Once the engine has reached the shift point, move the gearshift lever to the next lower lever position by double clutching.

Continue downshifting through the shift pattern by double clutching during shifts with the gearshift lever. Break torque during button shifts.

Eaton Top 2 Override with Cruise Control Switch

If this parameter is programmed to YES the cruise control On/Off switch can be used to disable Top 2 mode. If the cruise control On/Off switch is turned to the OFF position and the transmission is not in Top 2 mode, the Top 2 mode will be disabled. This condition is applicable to the manual mode of operation only. If the cruise control On/Off switch is turned to the ON position, the Top 2 mode will be enabled and the transmission will be allowed to shift automatically in the Top 2 gears. When the vehicle is operating in one of the Top 2 gears and the Top 2 mode is enabled, switching the cruise control On/Off switch to the OFF position will place the transmission in hold mode. When the transmission is in the Hold mode, the transmission will not shift out of the currently selected gear. When the cruise control On/Off switch is returned to the ON position, the transmission will return to Top 2 mode. When the clutch is depressed and the transmission is in the hold mode, the Manual mode will be enabled and the Top 2 will be disabled.

System Problems

If the system malfunctions, the transmission will typically default to manual operation. When the system is in manual operation, Top 2 is inactive. For some malfunctions, the system will detect a failure. When the system detects a failure, the operator must allow time out of the timer in the ECM. The ECM will complete the countdown in nine seconds. During the countdown, the ECM will try to complete the shift. Once the ECM has completed the countdown, the operator must place the transmission in neutral in order to obtain manual operation. The Top 2 function will be inactive until the vehicle is stopped and the key switch is turned off.

Wiring Connections Of The ECM

The control interface between the ECM and the Eaton Top 2 transmission consists of the following outputs:

• Eaton Top 2 shift solenoid (No. 7 Output)

• Eaton Top 2 lockout solenoid (No. 6 Output)

The ECM will turn on the Eaton Top 2 shift solenoid (No. 7 Output) when Top 2 is active in order to engage top gear. The ECM will turn off the Eaton Top 2 shift solenoid (No. 7 Output) at all other times, if the “Transmission Style” is programmed to Eaton Top 2.

The ECM will turn on the Eaton Top 2 lockout solenoid (No. 6 Output) when Top 2 is active in order to engage top gear minus one. The ECM will turn off the Eaton Top 2 lockout solenoid (No. 6 Output) at all other times, if the “Transmission Style” is programmed to Eaton Top 2.

Customer Specified Parameters

The following parameters must be programmed per the following list in order for the Eaton Top 2 transmission to function properly:
• “Transmission Style” Eaton Top 2
• “Top Gear Ratio” Programmed range 0.000 to 3.750
• “Top Gear Minus One Ratio” Programmed range 0.000 to 3.750
• “Top Gear Minus Two Ratio” Programmed range 0.000 to 3.750
• “Eaton Top 2 Override with Cruise Switch” Yes or No

Note: Each gear ratio must be precisely programmed to three decimal places per the following table for the model of transmission that is installed:

Note: The XX that appears in the model number of the transmission refers to the nominal torque capacity. XX times 100 equals the nominal torque capacity. For example, RTLO-14610B has a nominal torque capacity of 14 times 100 or 1900 N·m (1400 lb ft).

The model designation of the transmission and other information are stamped on a tag on the transmission. The tag is located on the lower left side near the front of the transmission.

Test Step 1. Check for Active/Logged Diagnostic Codes

A. Connect the electronic service tool to the data link connector.

B. Turn the key switch to the ON position.

C. Monitor the active diagnostic code screen on the electronic service tool.

D. Check and record active/logged diagnostic codes:
• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high
• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high
• 191-07 Transmission Not Responding

Note: If the “Eaton Top 2 Override With Cruise Switch” parameter is programmed to “YES” and the cruise control On/Off switch is in the OFF position, the operation of Top 2 is disabled.

Expected Result:
One or more of the listed codes are active or logged.

Results:
• 191-07 Only – Diagnostic code 191-07 is the only active diagnostic code or the only logged diagnostic code that is present. Proceed to Test Step 6.

• Any Code – Any single diagnostic code or any combination of diagnostic codes is present.

Proceed to Test Step 2.

• No Codes – If a transmission problem is still suspected, send the vehicle to the OEM dealer for service to the Eaton transmission. STOP. Test Step 2. Inspect Electrical Connectors and Wiring

A. Thoroughly inspect ECM vehicle harness connector J1/P1, the firewall bulkhead connector and the Eaton Top 2 solenoid connector. Refer to Troubleshooting, “Electrical Connectors – Inspect” for details.

B. Perform a 45 N (10 lb) pull test on each of the wires in the ECM connector that are associated with the Eaton Top 2 solenoids.

Refer to Illustration 79.

C. Check the ECM connector (Allen Head Screw) for the proper torque of 6.0 N·m (55 lb in).

D. Check the harness and wiring for abrasion and pinch points from the data link connectors back to the ECM.

Expected Result:
All connectors, pins and sockets should be completely coupled and/or inserted and the harness and wiring should be free of corrosion, abrasion or pinch points.

Results:
• OK – Proceed to Test Step 3.
• Not OK

Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.

Verify that the repair eliminates the problem.

STOP.

Test Step 3. Check the Solenoids

A. Connect the electronic service tool to the data link connector.

B. Turn the key switch to the ON position.

C. Access the customer specified parameters screen on the electronic service tool.

D. Verify that the “Transmission Style” is programmed to Eaton Top 2.

E. Access the special tests for the “Shift Solenoid” and the “Lockout Solenoid” on the electronic service tool. Access the following display screens in order:
• “Diagnostics”
• “Diagnostic Tests”
• “Special Tests”
• “Shift Solenoid” and “Lockout Solenoid”

F. Use the following procedure for either of the following active diagnostic codes or logged diagnostic codes:

• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high
a. Move the splitter button to the rear position.
b. Ensure that the air system pressure is equal to or greater than 620 kPa (90 psi).
c. While you listen for the solenoid to shift, cycle the special test for the “Shift Solenoid” from the ON position to the OFF position back to the ON position.

Note: You may need to be near the transmission in order to hear the shift.

G. Use the following procedure for either of the following active diagnostic codes or logged diagnostic codes:
• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high
a. Move the splitter button to the forward position.
b. Ensure that the air system pressure is equal to or greater than 620 kPa (90 psi).
c. While you listen for the solenoid to shift, cycle the special test for the “Lockout Solenoid” from the ON position to the OFF position back to the ON position.

Note: You may need to be near the transmission in order to hear the shift.

Note: 191-07 Transmission Not Responding may occur when one of the following diagnostic codes occurs during vehicle operation:
• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high
• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high

Expected Result:
The solenoid is operating correctly when the test is activated.

Results:
• OK – The ECM, the relay, and the solenoid are operating correctly.

Repair: Clear all logged diagnostic codes.

STOP.

• Not OK – Proceed to Test Step 4.

Test Step 4. Use the Special Test at the Solenoid Connector

A. Turn the key switch to the OFF position.

B. Disconnect the Eaton Top 2 solenoid connector.

C. Use the following procedure for either of the following active diagnostic codes or logged diagnostic codes:
• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high
a. Connect a voltage test lamp between pin “B” (Sensor Common) and pin “C” (No. 7 Output) on the ECM side of the Eaton Top 2 solenoid connector.

D. Connect the electronic service tool to the data link connector.

E. Turn the key switch to the ON position.

F. Access the special test for the “Shift Solenoid” on the electronic service tool. Access the following display screens in order:
• “Diagnostics”
• “Diagnostic Tests”
• “Special Test”
• “Shift Solenoid”

G. While you monitor the voltage test lamp, cycle the special test for the “Shift Solenoid” from the ON position to the OFF position and back to the ON position.

H. Stop the special test for the “Shift Solenoid”.

Note: When the key switch is turned on and the solenoid connector is disconnected, the following diagnostic code will occur during performance of the special test for the “Lockout Solenoid”:
• 54-05 Output #6 Open Circuit (66)
Clear this logged code when this step is completed.

I. Use the following procedure for either of the following active diagnostic codes or logged diagnostic codes:

• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high
a. Connect a voltage test lamp between pin “B” (Sensor Common) and pin “A” (No. 6 Output) on the ECM side of the Eaton Top 2 solenoid connector.

J. Connect the electronic service tool to the data link connector.

K. Turn the key switch to the ON position.

L. Access the special test for the “Shift Solenoid” and the “Lockout Solenoid” on the electronic service tool. Access the following display screens in order:
• “Diagnostics”
• “Diagnostic Tests”
• “Special Test”
• “Lockout Solenoid”

M. While you monitor the voltage test lamp, cycle the special test for the “Lockout Solenoid” from the ON position to the OFF position and back to the ON position.

N. Stop the special test for the “Lockout Solenoid”.

Note: When the key switch is turned on and the solenoid connector is disconnected, the following diagnostic code will occur during performance of the special test for the “Lockout Solenoid”:
• 55-05 Auxiliary Output #07 current low
Clear this logged code when this step is completed.

Expected Result:
The voltage test lamp behaves in the following manner:
• The voltage test lamp turns on when the test is active.
• The voltage test lamp turns off when the test is not active.

Results:
• OK – The engine harness and the ECM are OK.

Repair: Temporarily connect the suspect solenoids. Clear all logged diagnostic codes. Complete a test drive of the truck. If the diagnostic code is logged after attempting to use the Top 2 feature, replace the solenoids. Repeat the test drive in order to ensure that the problem has been corrected. Clear all logged diagnostic codes.

Verify that the repair eliminates the problem.

STOP.
• Not OK – The problem is in the harness wiring or the ECM. Remove the voltage test lamp. Proceed to Test Step 5.

Test Step 5. Use the Electronic Service Tool to Check the ECM

A. Turn the key switch to the OFF position.

B. Disconnect the ECM vehicle harness connector J1/P1.

C. Connect a 140-2266 Cable (Seventy-Pin Breakout) to the ECM connector J1.

D. Use the following procedure for either of the following diagnostic codes:
• 55-05 Auxiliary Output #07 current low
• 55-06 Auxiliary Output #07 current high
a. Remove terminal 20 from vehicle harness connector P1.
b. Connect P1 to the breakout T.

E. Connect a voltage test lamp to terminal 67 (?Battery) and terminal 20 (No. 7 Output) of the breakout T.
Note: The No. 7 Output is the shift solenoid.

F. Connect the electronic service tool to the data link connector.

G. Turn the key switch to the ON position.

H. Access the special test for the “Shift Solenoid” on the electronic service tool. Access the following display screens in order:
• “Diagnostics”
• “Diagnostic Tests”
• “Special Test”
• “Shift Solenoid”

I. While you monitor the voltage test lamp, cycle the special test for the “Shift Solenoid” from the ON position to the OFF position and back to the ON position.

J. Stop the special test for the “Shift Solenoid”.

K. Use the following procedure for either of the following diagnostic codes:
• 54-05 Auxiliary Output #06 current low
• 54-06 Auxiliary Output #06 current high
a. Remove terminal 19 from vehicle harness connector P1.
b. Connect P1 to the breakout T.

L. Connect a voltage test lamp to terminal 67 (?Battery) and terminal 19 (No. 6 Output) of the breakout T.

Note: The No. 6 Output is the lockout solenoid.

M. Connect the electronic service tool to the data link connector.

N. Turn the key switch to the ON position.

O. Access the special test for the “Lockout Solenoid” on the electronic service tool. Access the following display screens in order:
• “Diagnostics”
• “Diagnostic Tests”
• “Special Test”
• “Lockout Solenoid”

P. While you monitor the voltage test lamp, cycle the special test for the “Lockout Solenoid” from the ON position to the OFF position and back to the ON position.

Q. Stop the special test for the “Lockout Solenoid”.

Expected Result:
The voltage test lamp behaves in the following manner:
• The voltage test lamp turns on when the test is active.
• The voltage test lamp turns off when the test is not active.

Note: When all of the following conditions exist a 54-05 and 55-05 diagnostic code will occur:

• The key switch is turned on.
• The ECM connector J1/P1 is disconnected.
• The “Transmission Style” is programmed to Eaton Top 2.

This is normal. Clear these diagnostic codes after this test step is completed.

Results:
• OK

Repair: Clear any diagnostic codes that were caused during this step. Repair the vehicle harness from the Eaton Top 2 solenoid connector to ECM connector P1 or replace the vehicle harness from the Eaton Top 2 solenoid connector to ECM connector P1.

Verify that the repair eliminates the problem.

STOP.
• Not OK

Repair: Temporarily connect a test ECM. Remove all jumpers and replace all connectors. Recheck the system for active diagnostic codes. Repeat this test step. If the problem is resolved with the test ECM, reconnect the suspect ECM. If the problem returns with the suspect ECM, replace the ECM.

Verify that the repair eliminates the problem.

STOP.

Test Step 6. Check Gear Ratios

A. Connect the electronic service tool to the data link connector.

B. Turn the key switch to the ON position.

C. Access the customer specified parameters screen on the electronic service tool.

D. Verify that the three parameters for gear ratios are correctly programmed.

Refer to Table 148.

Expected Result:
The parameters for the gear ratios are programmed correctly.

Results:
• OK

Repair: If a transmission problem is still suspected, send the vehicle to the OEM dealer for service to the Eaton Transmission.

STOP.
• Not OK

Repair: Consult the OEM dealer in order to determine the proper values for the gear ratios and program the proper values for the gear ratios. STOP.

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