P2703
P2703-INADEQUATE ELEMENT VOLUME UD
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The volumes of the transmission fluid needed to apply the friction elements are continuously monitored and learned for adaptive controls. As the clutch friction material wears, the volume of fluid needed to apply the clutch increases. Certain transmission mechanical problems can cause near-zero learned volumes resulting in setting a DTC. The DTC will usually set with other DTCs, which indicates an internal transmission problem.
- When Monitored:
Whenever the engine is running. The UD clutch volume index (CVI) is updated during a 4-3 kickdown with throttle angle between 10 and 54 degrees. Transmission temperature must be at least 43° C (110° F).
- Set Condition:
When the UD CVI falls below 11.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.
1. OTHER DTCS PRESENT
1. With the scan tool, check DTCs.
Are there any Pressure Switch Sense circuit DTCs present also?
Yes
- Testing and InspectionPerform the appropriate diagnostic procedure.
No
- Go To 2
2. CHECK UD CLUTCH VOLUME INDEX
1. With the scan tool, erase Transmission DTCs.
NOTE: The TRANS TEMP DEG must be at least 43° C or 110° F before performing the following steps.
2. Drive the vehicle and perform at least ten 4-3 kickdowns by depressing the throttle between 30 and 54 TPS degrees at speeds about 80 Km/h or 50 mph.
3. With the scan tool, read the UD clutch volume index (CVI).
Is the UD CVI below 10?
Yes
- Go To 3
No
- Go To 5
3. UD CLUTCH CIRCUIT LEAKS IN THE VALVE BODY
1. Turn the ignition off to the lock position.
2. Remove the transmission oil pan and valve body.
3. Check the condition of the UD accumulator springs.
4. Look for possible leak paths into the UD clutch hydraulics circuit within the valve body.
Were there any problems found?
Yes
- Repair as necessary. Valve Body - Removal.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. . 545RFE Transmission Verification Test
No
- Go To 4
4. AIR CHECK UD CLUTCH CIRCUIT
1. Perform an air check on the UD Clutch circuit.
2. Watch and listen for UD Clutch piston movement.
3. Air check all other pump passages for air leakage into the UD Clutch circuit.
Were any problems found?
Yes
- Repair internal transmission. Pay attention to components related to the UD clutch. Broken or weak return spring or a dislocated snap ring. If no trouble is found in UD clutch component or UD clutch leakage was noted in passage, replace the Pump Assembly. Removal.
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. . 545RFE Transmission Verification Test
No
- Replace the Transmission/TRS Solenoid Assembly. With the scan tool, perform Quick Learn. . Quick Learn Procedure
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. . 545RFE Transmission Verification Test
5. VERIFY PCM OPERATION
NOTE: The TRANS TEMP DEG must be at least 43° C or 110° F before performing the following steps.
1. Perform eight learnable starts. A learnable start is defined as follows: Start engine. From a standstill, accelerate lightly to 80 Km/h or 50 mph, then brake lightly to a stop. Turn off engine.
2. With the scan tool, record the clutch volume index (CVI) for all clutches.
3. With the scan tool, perform a BATTERY DISCONNECT.
4. With the scan tool, read the CVIs and compare them to the readings recorded before the BATTERY DISCONNECT.
Are any of the CVIs less than 5 or different than before the BATTERY DISCONNECT?
Yes
- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the PCM. With the scan tool, perform Quick Learn. . Quick Learn Procedure
- Perform the 545RFE TRANSMISSION VERIFICATION TEST. . 545RFE Transmission Verification Test
No
- Test Complete.