P0732-GEAR RATIO ERROR IN 2ND

For a complete wiring diagram Refer to Section 8W

Theory of Operation


The transmission system uses two speed sensors, one to measure input RPM and one to measure output RPM. These inputs are essential for proper transmission operation. Therefore, the integrity of this data is verified through the following checks:

1) Once in a particular gear, if the gear ratio varies from the correct gear ratio, the corresponding in-gear trouble code is set (DTCs P0731-36).

2) An excessive change in input or output speeds indicating signal intermittent may result in the DTCs P0715 and/or P0720 being set.

3) If the common speed sensor ground circuit is lost, both sensor inputs will read the pulses from the input speed sensor when at a stop in neutral. Since the input speed sensor reads 60 teeth from the input clutch hub and the output speed sensor reads 30 teeth from the park gear, the result is an apparent speed ratio of 1:2 and may cause the DTC P1794 to set.


  • When Monitored:

    Continuously with the ignition on, engine running, with the transmission in gear.

  • Set Condition:

    If the ratio of the Input RPM to the Output RPM does not match the current gear ratio. This DTC can take up to five minutes of problem identification before illuminating the MIL


Possible Causes
  
RELATED DTC'S PRESENT
  
INPUT SPEED SENSOR OR WIRING
  
LOW FLUID LEVEL
  
CRACKED OR MIS-INSTALLED PRIMARY OIL FILTER OR SEAL
  
WORN SOLENOID SWITCH VALVE OR PLUGS
  
STUCK OR STICKING MAIN REGULATOR VALVE
  
BURNED UD OR 2C CLUTCH
  
CUT 2C OR UD PISTON SEAL
  
BROKEN 2C PISTON CASTING
  
BROKEN OR MISSING 2C BLEED ORIFICE
  
BROKEN OR MISSING UD BLEED ORIFICE
  
CUT 2C OR UD ACCUMULATOR PISTON SEAL
  
CRACKED 2C OR UD ACCUMULATOR PISTON
  
CUT OR MISSING #5 OR #7 CHECK BALL
  
TRANSMISSION SOLENOID/TRS ASSEMBLY
  
BROKEN WELD - REACTION CARRIER TO REVERSE SUN GEAR
  
MISSING TEETH ON INPUT CLUTCH HUB TONE WHEEL
  

Always perform the 45RFE/545RFE Pre-Diagnostic Troubleshooting Procedure before proceeding. (Refer to 21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)



Diagnostic Test

1.CHECK FOR RELATED DTCS



Are there any Transmission: solenoid, line pressure, speed sensor, and/or loss of prime DTCs present?

Yes
  • Refer to appropriate symptom in the Transmission category. Perform the test for P0944-LOSS OF PRIME first if it is present.


No
  • Go To 2

2.CHECK IF DTC IS CURRENT


NOTE: Make sure to record all DTC EVENT DATA stored in the scan tool for future reference in this test procedure.



Does the DTC EVENT DATA display information for the DTC P0732?

Yes
  • Go To 4


No
  • Go To 3

3.CHECK DTC EVENT DATA



Does the DTC EVENT DATA display information for the DTC P1790, with target gear = 2nd, or with both 2C and UD clutches applying?

Yes
  • Go To 4


No
  • Go To 7

4.CHECK RPM IN DTC EVENT DATA



Does the Input RPM read zero?

Yes
  • Check the input speed sensor and wiring. Refer to test P0715 and diagnose as if the DTC is current.


No
  • Go To 5

5.CHECK LINE PRESSURE READING



Is the line pressure reading more than 10 psi below the desired line pressure?

Yes
  • Go To 6


No
  • Go To7

6.CHECK TRANSMISSION OIL FILTER




NOTE: Make sure the Primary Transmission Oil Filter and seal are properly installed and are not cracked or split.



Does the Oil Pan contain excessive debris and/or is the Primary Oil Filter cracked, plugged or mis-installed?

Yes


No

7.CHECK IF THE DTC P0732 IS CURRENT



CAUTION: Do not overheat the transmission.


NOTE: If the 2C clutch is faulty, the overrunning clutch will hold and the slip test will pass. The 2nd gear clutch test will not detect a faulty 2C clutch. However, it will detect a faulty UD clutch.



Did the clutch test pass, did the Input Speed remain at zero?

Yes
  • Go To 8


No

8.CHECK FOR INTERMITTENT OPERATION





Were there any problems found?

Yes


No
  • Go To 9

9.CHECK FOR SLIPPAGE




Is there an obvious slippage noticed in 2nd gear, or runaway on the 1–2 shift?

Yes


No

10.CHECK THE UD HYDRAULIC CLUTCH CIRCUIT



NOTE: The UD clutch passage contains a small bleed orifice, a small amount of air leakage is normal.



Were there any problems found, excessive debris and/or excessive air leakage in the UD clutch hydraulic circuit?

Yes


No

11.CHECK THE UD ACCUMULATOR PISTON



Were there any problems found?

Yes


No

12.CHECK FOR EXCESSIVE DEBRIS




NOTE: The 2C clutch passage contains a small bleed orifice, a small amount of air leakage is normal.



Were there any problems found, excessive debris, improperly assembled 2C clutch and/or excessive air leakage in the 2C hydraulic clutch circuit?

Yes


No

13.CHECK THE 2C ACCUMULATOR





Were there any problems found

Yes


No

14.CHECK FOR BROKEN REVERSE SUN GEAR WELD






Is the reaction carrier turning faster than the drive shell?

Yes


No

15.CHECK IF DTC RESETS


Did the DTC P0732 reset during the road test?

Yes


No

16.LIST OF POSSIBLE CAUSES


  • Check for excessive debris in the Transmission Oil pan, plugged, cracked, or misinstalled Primary Transmission Oil Filter and/or seal.
  • Check for cut and/or missing #7 and #5 check balls in the main valve body.
  • Check the 2C and UD accumulator pistons and seals, UD bleed orifice, and the Solenoid Switch Valve and Plugs in the main valve body.
  • Check the UD clutch piston seals, reaction shaft support seal rings and dribbler assembly.
  • Check the 2C clutch piston seals, and bleed orifice.
  • Check the main regulator valve for sticking in its bore and the flatness of the pump valve body and pump housing faces.
  • Check for a improperly assembled 2C clutch with the thick reaction plate not against the case.


View repair

Repair

17.INTERMITTENT DTC


  • If the DTC Event Data shows fault P0732 was set in Park, Reverse, or Neutral, replace the Powertrain Control Module.
  • If the DTC Event Data shows fault P0732 set with input RPM = zero, check the input speed sensor and related wiring.
  • If the DTC Event Data shows fault P0732 set with line pressure significantly below desired line pressure, check for the cause of low line pressure (i.e., oil level, misinstalled or damaged primary filter or filter seal, sticking main regulator valve in pump, etc.).
  • If the DTC Event Data shows fault P0732 set with the UD or 2C pressure switch open (but line pressure matches Desired Line Pressure), air check the UD and 2C hydraulic clutch circuits for leakage per the Service Information. If the UD and 2C hydraulic clutch circuits are OK, replace the Transmission Solenoid/TRS assembly.




CAUTION: Removal of the Starter Relay will prevent the vehicle from being started in gear.


WARNING: The Starter Relay must be removed from the PDC. Failure to do so can result in personal injury or death.


NOTE: Failure to remove the Starter Relay can cause a Transmission - No Response condition.







Were there any problems found.

Yes


No
  • Test Complete.