Challenger 35, Challenger 45 and Challenger 55 Agricultural Tractors Power Train Caterpillar

Troubleshooting the Transmission

Problem List

• "The Machine does not Move in any Speed"

• "The Transmission does not Shift into all of the Speeds"

• "The Filter Indicator Flashes"

• "The Transmission Shifts too Hard"

• "The Engine stops"

• "The Transmission Oil Temperature Indicator Light is on"

• "The Transmission Locks in a Speed"

• "The Transmission Slips"

• "The Inching Clutch Control does not work Properly"

• "The Charge Pressure is Low"

• "The PTO will not Engage"

• "The PTO will not Disengage"

• "The PTO is not Modulated During Engagement"

Probable Causes

The Machine does not Move in any Speed

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level - Check".

3. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation/Testing and Adjusting, "Transmission Clutch Calibration".

4. Repair any problems that are found in the calibration procedure.

   Note: Operate the machine. If the transmission does not function properly, continue with Step 5.

5. Perform the pressure tests for the transmission. Refer to Systems Operation/Testing and Adjusting, "Pressure Tests".

6. Repair any failed components that are found while you perform the pressure tests.

The Transmission does not Shift into all of the Speeds

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level - Check".

3. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation and Testing and Adjusting, "Transmission Clutch Calibration".

4. Repair any failed components or replace any failed components that are found during the calibration procedure.

   Note: Operate the machine. If the transmission does not function properly, continue with Step 5.

5. Perform the pressure tests for the transmission. Refer to Systems Operation and Testing and Adjusting, "Pressure Tests".

6. Repair any failed components or replace any failed components that are found during the pressure tests.

7. If a certain speed is missing, identify the clutches that are used for that speed. See Table 1 for the clutches that are used in each speed. Look for a speed that uses similar clutches. Exchange one solenoid valve at a time from a speed that is known to work. For example, if "F1" speed is missing and "F2" speed is working exchange the solenoid valves from clutches "1" and "2". This will isolate the faulty solenoid valve. Replace any faulty solenoid valves that are found during the test.

The Filter Indicator Flashes

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Illustration 1	g00506153

1. Replace the hydraulic filters. Refer to Operation and Maintenance Manual, "Hydraulic Filters - Replace".

2. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

The Transmission Shifts too Hard

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level ".

3. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation and Testing and Adjusting, "Transmission Clutch Calibration".

4. Repair any problems that are found in the calibration procedure.

   Note: Operate the machine. If the transmission does not function properly, continue with Step 5.

5. Use Table 1 in order to determine the modulator solenoid that is used for each speed.
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   Table 1

   Transmission Speed	Modulator Solenoid	Clutches that are Engaged
   F1	MC1	1	A	F1
   F2	MC1	2	A	F1
   F3	MC1	3	A	F1
   F4	MC1	1	B	F1
   F5	MC1	2	B	F1
   F6	MC1	3	B	F1
   F7	MC1	1	C	F1
   F8 (1)	MC1	2	C	F1
   F8 (2)	MC2	1	A	F2
   F9 (1)	MC1	3	C	F1
   F9 (2)	MC2	2	A	F2
   F10	MC2	3	A	F2
   F11	MC2	1	B	F2
   F12	MC2	2	B	F2
   F13	MC2	3	B	F2
   F14	MC2	1	C	F2
   F15	MC2	2	C	F2
   F16	MC2	2	C	F2
   R3	MC2	1	A	R
   R4	MC2	2	A	R
   R5	MC2	3	A	R
   R6	MC2	1	B	R
   R7	MC2	2	B	R
   R8	MC2	3	B	R
   R9	MC2	1	C	R
   R10	MC2	2	C	R
   R11	MC2	3	C	R

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   ( 1 )	Up shift
   ( 2 )	Down shift

6. Test the modulation pressure for the speed that is shifting too hard. Refer to Systems Operation and Testing and Adjusting, "Pressure Tests".

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Illustration 2	g00637879

7. Remove the modulator solenoid. Check spool (1) and check spring (2) .

8. Replace the spool and replace the spring, if necessary.

The Transmission Oil Pressure Indicator is On

Illustration 3	g00506149

If the transmission pressure is below 830 kPa (120 psi) for more than 30 seconds the engine will stop.

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

   Note: Operate the machine. If the transmission oil pressure indicator is still on, continue with Step 2.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level ".

3. Check the pressure of the transmission. Adjust the pressure of the transmission, if necessary. Refer to Systems Operation/Testing and Adjusting, "Pressure Tests".

The Engine stops

1. If the Transmission Oil Pressure Indicator is illuminated continuously for 30 seconds, the engine will stop. If the temperature indicator for the transmission is illuminated continuously for 30 seconds, the engine will stop.

2. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

3. When the problem is corrected, operate the machine in order to verify that the problem is corrected.

The Transmission Oil Temperature Indicator Light is on

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Illustration 4	g00506148

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level ".

3. Check the hydraulic oil cooler.

   1. Check the cooler for dirt or foreign material. Clean the cooler, if necessary.

   2. Check the cooler for damage. As required, repair components or replace components.

   3. Check the cooler lines for damage. As required, repair components or replace components.

4. Air flow across the cooler is low.

   1. Check the fan for damage. If the fan is damaged, replace the fan.

   2. Check the fan drive belt. The speed of the fan may be reduced if the fan drive belt is loose or if the fan drive belt is damaged. If the fan drive belt is damaged, replace the belt.

5. There is air in the oil. Find the location of the entry of the air into the system. As required, repair components or replace components.

6. There is a problem with the implement hydraulic system or there is a problem with the steering hydraulic system. Refer to Systems Operation/Testing and Adjusting, "Troubleshooting".

The Transmission Locks in a Speed

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Find the speed that is locked. Find the clutches that are used to engage the speed. Use Table 1 to find the clutches that are used to engage each speed. Test the pressures of the clutches. Refer to Systems Operation/Testing and Adjusting, "Pressure Tests".

The Transmission Slips

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Check the reservoir for the correct type of oil and check the reservoir for the correct quantity of oil. Refer to Operation and Maintenance Manual, "Hydraulic System Oil Level ".

3. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation and Testing and Adjusting, "Transmission Clutch Calibration".

4. Repair any problems that are found in the calibration procedure.

5. Perform the pressure tests for the transmission. Refer to Systems Operation and Testing and Adjusting, "Pressure Tests".

6. Repair any problems that are found during the pressure tests.

7. If the pressure is correct, the clutches may be worn. As required, repair components or replace components.

The Inching Clutch Control does not work Properly

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Perform the calibration procedure for the transmission clutch. Refer to Systems Operation and Testing and Adjusting, "Transmission Clutch Calibration".

The Charge Pressure is Low

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Perform the pressure tests for the transmission. Refer to Systems Operation/Testing and Adjusting, "Pressure Tests".

The PTO will not Engage

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

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Illustration 5	g00504291
(3) Brake (4) Piston (5) Spring (6) Solenoid (7) Spool (8) Orifice (9) Orifice (10) Clutch (11) Spring (12) Orifice

2. Solenoid (6) has failed. Test the solenoid. Refer to Systems Operation and Testing and Adjusting, RENR1781.

3. Spool (7) is stuck. Test the pressure of the PTO. Refer to Systems Operation/Testing and Adjusting, "PTO Pressure Tests". Repair the spool or replace the spool, if necessary.

4. The seals for clutch pack (10) are leaking. Refer to Systems Operation/Testing and Adjusting, "PTO Pressure Tests". Replace the seals for the clutch pack, if necessary.

The PTO will not Disengage

Illustration 6	g00504291
(3) Brake (4) Piston (5) Spring (6) Solenoid (7) Spool (8) Orifice (9) Orifice (10) Clutch (11) Spring (12) Orifice

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Solenoid (6) is leaking. Test the pressure of the PTO. Refer to Systems Operation/Testing and Adjusting, "Power Take Off (PTO) Pressure Tests - Test and Adjust". Replace the seals for the clutch pack, if necessary.

3. Brake piston (4) has failed. Repair the piston or replace the piston.

4. The brake for the PTO has failed. Replace the brake for the PTO.

5. Return spring (5) has failed. Repair the spring or replace the spring.

The PTO is not Modulated During Engagement

Illustration 7	g00504291
(3) Brake (4) Piston (5) Spring (6) Solenoid (7) Spool (8) Orifice (9) Orifice (10) Clutch (11) Spring (12) Orifice

1. Check the fault codes in mode two of the Machine Performance Monitor. See Systems Operation/Testing and Adjusting, RENR1781, "Electronic Systems" for more information. Repair any active faults that are displayed.

2. Test the modulation pressure of the clutch. Refer to Systems Operation/Testing and Adjusting, "Power Take Off (PTO) Pressure Tests - Test and Adjust".

   If the modulation pressure is not correct, check for one of the following conditions.

   1. Orifice (8) is plugged. Clean the orifice.

   2. Orifice (9) is plugged. Clean the orifice.

   3. Orifice (12) is plugged. Clean the orifice.

   4. Spring (11) has failed. Replace the spring.