Diagnostic Instructions
DTC Descriptor
DTC P0735: Incorrect 5th Gear Ratio
Circuit/System Description
The transmission control module (TCM) calculates the actual gear ratio based on input speed sensor (ISS) and output speed sensor (OSS) data. The actual gear ratio is compared to the expected gear ratio for each commanded gear.
If the TCM detects an incorrect 5th gear ratio while in 5th gear, DTC P0735 sets.
Conditions for Running the DTC
• | No Throttle Position (TP) Sensor DTC P0120. |
• | No Transmission Range (TR) Switch DTCs P0706, P0707, or P0708. |
• | No Transmission Fluid Temperature (TFT) Sensor DTCs P0711, P0712, or P0713. |
• | No Speed Sensor DTCs P0717, P0722, or P0727. |
• | No Pressure Control (PC) Solenoid DTCs P0962, P0963, P0966, P0967, P0970, or P0971. |
• | No Shift Solenoid (SS) Control Circuit DTCs P0973, P0974, P0976, P0977, P0979, P0980, P0982, P0983, P0985, or P0986. |
• | No Transmission Torque Delivered Circuit DTC P2637. |
• | No Communications DTCs U0100 or U2104. |
• | Output speed greater than one half that of the input speed. |
• | Input speed is greater than 400 RPM. |
• | Current gear equals 5th. |
• | Transmission fluid temperature (TFT) is greater than 20°C (68°F). |
• | Engine speed is greater than 400 RPM. |
• | Throttle position greater than 10 percent. |
• | Shift range equals D, M, or L for at least 2 seconds. |
• | Ignition voltage is greater than 10.5 volts. |
Conditions for Setting the DTC
The following condition is met for 1 second, 12 occurrences.
The current ratio and the expected ratio differ by more than 20 percent.
Action Taken When the DTC Sets
• | DTC P0735 is a Type A DTC. |
• | Limit engine torque to 150 N·m (111 lb ft). |
Conditions for Clearing the DTC
DTC P0735 is a Type A DTC.
Diagnostic Aids
Improper transmission fluid level may cause DTC P0735 to set. Refer to the
Transmission Fluid Check procedure.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Scan Tool Reference
Control Module References for scan information.
Circuit/System Verification
- Ignition ON, observe the DTC information with a scan tool.
- Record Freeze Frame and Failure Records.
- Clear DTCs.
- Operate the vehicle under the conditions observed in the Failure Records.
- Observe the DTC information with the scan tool. Verify that the DTC does not set.
Circuit/System Testing
- Operate the vehicle in D.
- Using the scan tool record the gear ratio while accelerating in 4th gear. The gear ratio should be within 1.04:1-1.56:1.
• | Stuck 2-3, 3-4 shift solenoid valve assembly |
⇒ | If the 4th gear ratio is not within the specified range and is not 1.00:1, continue to step 3. |
- Observe the scan tool Transmission OSS parameter while driving the vehicle. The reading should correspond to a known properly functioning OSS.
- Stop the vehicle, apply the parking brake, engine at idle, select P (park) using the Shift Control.
- Observe the scan tool Transmission ISS parameter. The reading should be within 400-800 RPM.
⇒ | If the ISS parameter is not within the specified range, replace the Transmission Input Speed Sensor (ISS). Refer to the
Input Speed Sensor Replacement procedure. |
- Ignition ON, engine OFF, command shift solenoid 1 ON and OFF with a scan tool. The solenoid should click when commanded ON.
- Command shift solenoid 3 ON and OFF with a scan tool. The solenoid should click when commanded ON.
- Perform a line pressure test. Refer to
Line Pressure Check procedure.
- Remove the control valve body cover. Refer to
Control Valve Body Cover Removal procedure.
- Inspect the inside of the control valve body cover for excessive sediment. There should not be excessive sediment.
- Inspect the control valve body assembly for the following conditions. Refer to
Control Valve Rear Body Disassemble and
Control Valve Body Disassemble - Middle . The conditions should not be found.
• | Stuck shift pressure relay valve |
• | Stuck neutral relay valve |
• | Stuck line pressure control solenoid valve assembly |
- Verify that the control valve body has been serviced within the past 3 months.
- If all circuits and components test normal, replace the transmission.
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.