Relays
There are two relays in the system that are activated directly by the Transmission ECU. The relays are the start relay and the backup alarm relay.
Start Relay
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| Illustration 1 | g01251477 |
This relay prevents the engagement of the starter if the engine is already running. When the keyswitch is moved to the start position, the transmission control verifies the transmission is in neutral and the engine is not already running. If these conditions are met, the transmission control will energize the start relay. The relay is controlled by the neutral start function.
Backup Alarm Relay
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| Illustration 2 | g01230721 |
Backup alarm is active whenever the shift lever / shuttle handle is in REVERSE.
Solenoids
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| Illustration 3 | g01237747 |
The solenoid valves are an output of the Transmission ECU. The solenoid is the proportional type. The ECU uses a pulse width modulated signal (PWM) to vary the current to the solenoid. The distance that is travelled by the solenoid valve is proportional to the electrical current. The position of the valve opens or the position of the valve blocks the flow of oil to the hydraulic cylinder.
Solenoids control the oil flow to the clutches in the transmission. When a direction and gear are selected by the operator, the control module activates the appropriate solenoids. Two solenoids are activated in order to move the machine. One solenoid is activated for the direction and one solenoid is activated for the gear. When a solenoid is activated, a solenoid receives voltage from the control module. When the transmission is in neutral, no solenoids are activated.
The solenoids have a connector with 2 contacts. One contact receives power from the corresponding connector contact (signal) of the control module. The other contact returns to the control module. All of the solenoids have a return lead. The return leads join together with the other return leads.
Transmission Lockup Clutch Solenoid
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| Illustration 4 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-50. The signal contact is connected to the ECU through contact J1-62.
Transmission Shift #1 Solenoid
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| Illustration 5 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-50. The signal contact is connected to the ECU through contact J1-59.
Transmission Shift #2 Solenoid
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| Illustration 6 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-60. The signal contact is connected to the ECU through contact J1-49.
Transmission Shift #3 Solenoid
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| Illustration 7 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-60. The signal contact is connected to the ECU through contact J1-51.
Transmission Shift #4 Solenoid
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| Illustration 8 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-60. The signal contact is connected to the ECU through contact J1-52.
Transmission Shift #5 Solenoid
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| Illustration 9 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-50. The signal contact is connected to the ECU through contact J1-48.
Transmission Shift #6 Solenoid
Note: This solenoid is available on the TH35 Transmission Only.
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| Illustration 10 | g01237747 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-50. The signal contact is connected to the ECU through contact J1-48.
Engage Solenoid
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| Illustration 11 | g01297190 |
The following solenoids are associated with the dropbox:
- Work mode engage solenoid
- Front wheel drive engage solenoid
- Rear wheel drive engage solenoid
Work mode engage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-55. The signal contact is connected to the ECU through contact J1-65.
Front wheel drive engage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J2-8. The signal contact is connected to the ECU through contact J2-2.
Rear wheel drive engage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-55. The signal contact is connected to the ECU through contact J1-67.
Disengage Solenoid
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| Illustration 12 | g01297194 |
The following solenoids are associated with the dropbox:
- Work mode disengage solenoid
- Front wheel drive disengage solenoid
- Rear wheel drive disengage solenoid
Each disconnect has one engage and one disengage electrohydraulic valve and solenoid. The disengage solenoid is energized when the disconnect is to be disengaged. The engage solenoid is energized when the disconnect is to be engaged.
Work mode disengage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-66. The signal contact is connected to the ECU through contact J1-65.
Front wheel drive disengage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J2-6. The signal contact is connected to the ECU through contact J2-8.
Rear wheel drive disengage - The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-68. The signal contact is connected to the ECU through contact J1-65.
Retarder Solenoid (Optional)
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| Illustration 13 | g01297194 |
The solenoid has a connector with two contacts. The sensor ground is connected to the ECU through contact J1-60. The signal contact is connected to the ECU through contact J1-61.
Indicators
Powertrain Warning LED
The LED is one that turns on when there is a level 1, 2, and 3 warning event. This is for the truck OEM's that will put a red transmission warning LED in the dash.