Transmission problems my 05 t&c will not change gear while driving . it was put on the machine which said it was the tcm module but when I took it to a transmission shop they said their machine said the same thing but when they checked it they said that it wasn't the tcm but didn't know what it was! t t bu t t t

troubleshoot this further:

Check Transmission Fluid:
The first step is to inspect the transmission fluid. Low or contaminated fluid can lead to poor shifting performance. Ensure the fluid levels are adequate and replace it if necessary.

Throttle Position Sensors and Shift Solenoids:
Misaligned throttle position sensors or malfunctioning shift solenoids could be causing the gear shifting problems. These components play a crucial role in proper gear changes. A professional diagnosis is recommended. It is not unusal for a defective solenoid to render this effect.

Transmission Control Module (TCM):
The TCM manages the transmission's operation, including gear shifting. If it's malfunctioning, it can lead to incorrect or no gear shifts. Consider checking or replacing the TCM.

Shift Linkage or Cable Issues:
Damaged or worn shift linkage or cables can also cause gear shifting problems. These components connect the gear shift lever to the transmission. Inspect and replace any damaged parts.
Remember that diagnosing transmission issues usually requires professional expertise.

There could be several issues that could cause your GMC Envoy's transmission to not shift gears properly and the RPMs to rev high. Here are a few potential problems that you may want to consider:

1. Low transmission fluid: If the transmission fluid is low, it could cause problems with the shifting mechanism. You'll want to check the transmission fluid level and add more if needed.
2. Faulty shift solenoid: The shift solenoid is responsible for directing transmission fluid to the appropriate gear. If the solenoid is faulty, it could cause shifting problems.
3. Worn transmission bands or gears: If the transmission bands or gears are worn, it could cause the transmission to not shift properly and the RPMs to rev high.
4. Clogged transmission filter: A clogged transmission filter can restrict the flow of transmission fluid, causing shifting issues.
5. Faulty transmission control module (TCM): The TCM is responsible for controlling the transmission. If it's not functioning properly, it could cause shifting problems.

I would recommend having a mechanic diagnose and fix the problem for you. It's important to address transmission issues promptly, as they can lead to further damage if left unchecked.

There could be several reasons why your 2005 Dodge Magnum is experiencing problems with shifting from second to third gear and then suddenly hitting reverse, including:

1. Transmission Fluid Level: Low transmission fluid level can cause erratic shifting, slipping, or stalling in your vehicle. Make sure to check your transmission fluid level and add if necessary.
2. Shift Solenoid: A faulty shift solenoid can cause problems with shifting in your transmission. The solenoids control the flow of transmission fluid through the valve body, which controls the shifting of gears. If the shift solenoid is failing or has failed, it can cause the transmission to slip, shift erratically, or get stuck in a gear.
3. Transmission Pump: The transmission pump is responsible for pumping transmission fluid through the transmission and to the torque converter. If the pump is failing, it may not be able to pump fluid properly, leading to problems with shifting and slippage.
4. Valve Body: The valve body controls the flow of transmission fluid through the transmission and directs the shifting of gears. If the valve body is failing, it can cause the transmission to shift erratically or get stuck in a gear.
5. Transmission Control Module (TCM): The TCM is responsible for controlling the transmission's shifting and overall performance. If the TCM is failing, it can cause the transmission to shift erratically or get stuck in a gear.

It's best to have a qualified mechanic diagnose and repair the issue as they will have the necessary tools and expertise to properly diagnose and fix the issue.

Well code 700 is a generic code that means there is a problem with the transmission or the control module. Code 731 is for a problem with first gear which would explain why it stays in second gear.
Someone will need to check the circuits involved with first gear and the trans control module. A shop manual will be necessary to get the testing procedures.

Here is the definition for the code.

P0736 MITSUBISHI Description This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:

Torque converter slip ratio = A x C/B

A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes
Possible causes - Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit
Read more: http://engine-codes.com/p0736_mitsubishi.html#ixzz27FemXvl5

Hi Mati:
Diagnostic trouble code (DTC) TCM-000C is stored if the control module detects that the vehicle speed and engine speed (RPM) signals do not correspond with the programmed values and that an "incorrect" gear is being used in relation to the calculated gear. This is because solenoid S2 is stuck in open or closed position.

Diagnostic Codes: 000C, 002A, 002B, P0733, P0734, P0756
Tests/Procedures:
1. Clear codes from the Transmission Control Module (TCM).
2. With fluid hot, check transmission fluid for quality and level.
3. Test drive the vehicle. Accelerate from 20-60 MPH when in geartronic mode, gear 4. While doing this, watch input and output speed sensors with a scan tool.
4. If the code returns, the transmission is slipping, and the input and output speed sensors are updating, the problem is internal to the transmission.
5. If transmission is replaced, test ATF for coolant contamination per TNN 43-48. Replace radiator if necessary.

Potential Causes: Transmission Mechanical Problem

Tech Tips:
TCM-002B 4th gear. Incorrect gear ratio. This code sets when the actual gear ratio deviates by more than 10% of what is programmed into the TCM.
TCM-002A 3rd gear. Incorrect gear ratio P0756 - TCM-000C - Shift solenoid S2, hydraulic malfunction If the transmission is replaced, be sure the mating surfaces between the engine and transmission are bare metal and clean. If not, the engine may not start after assembly.

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DTC P0734 - Improper Ratio for Fourth Gear.
P0734 is detected when A/T cannot be shifted to the 4th gear position even if electrical circuit is good.

This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:

Torque converter slip ratio = A x C/B

A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes

If the actual gear position is higher than the position (4th) supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.

Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Incorrect transmission shifting

Possible causes
- Low transmission fluid level
- Dirty transmission fluid
- Shift solenoids
- Transmission mechanical problems
- Transmission hydraulic control circuit

Tech notes: Start by inspecting the transmission fluid level and condition, and change fluid if necessary.


Test and check it and send us ypur comments.

Where is the TCM?

Before condemning the transmission, I would check the shift cable for proper operation. Look at the side of the transmission where the shift cable attaches. Have someone shift the transmission from PARK to FIRST. The engine should not be running. If the operating lever on the transmission moves, then you probably do have an internal transmission problem.
If the operating lever does not move, you have a broken shift cable or it has popped of it's attachments at the operating lever or gear shift handle.

A bad Transmission Control Module (TCM) would not keep it from shifting. In the event of a bad TCM, the transmission would go into fail safe mode and you could continue driving the vehicle.