You’re most likely here because your transmission will not engage in any gear. When you put it into drive or reverse, the car doesn’t move. It feels like your emergency brake is engaged. Even your engine revs up but the car makes no motion.
In this post, we’ll be looking at the different possible reasons why this problem occurs and how you can diagnose and fix them.
Table of contents
- Reasons Why Your Transmission Will Not Engage in Any Gear
- How To Fix Transmission Engaging Problems
Reasons Why Your Transmission Will Not Engage in Any Gear
1. Transmission Fluid
First, check the fluid level and look at the color of your transmission fluid. If the level is below the minimum, top off with a 50/50 mix of new oil and ATF (automatic transmission fluid). If your transmission fluid is dirty or low, it might be the reason why your transmission does not engage in any gear.
Next, check your automatic transmission fluid type to make sure it is appropriate for your vehicle. Some manufacturers recommend using synthetic or semi-synthetic fluids while others recommend conventional mineral oils. Your owner’s manual will tell you what type to use in order to protect your engine and maximize its lifespan.
Checking this information will help you determine whether or not you need more than just a simple bottle of fluid—you may also need a transmission flush kit for cleaning purposes before putting in new liquid.
2. Broken or Damaged Wiring
Check for broken or damaged wiring. Inspect the wiring harness and battery cables. Look for any damage to the wires, including chafed insulation or exposed metal. If you see any signs of damage, repair it before continuing with this test.
Check for loose or broken wires. Check that all battery cables are securely connected to their terminals and tighten the connections if needed.
Make sure that there is a clear connection between each terminal and its corresponding cable end by gently pulling on them; if they come apart easily, tighten them again until they do not budge when tugged on gently but firmly.
3. Bad Torque Converter Solenoid
The torque converter solenoid is responsible for controlling the fluid pressure in your transmission, and it can be damaged if you shift into gear too quickly or forcefully.
If it’s damaged, you may not be able to put the car into gear at all. It can also cause problems with shifting gears once you have shifted them; if this happens, you will probably notice that your car feels like it is slipping.
4. Internal Issues with The Transmission
If you don’t have any external transmission problems, it can be helpful to check for internal issues with your transmission. The fluid in your transmission is what lubricates and cools the gears inside of it. If that fluid gets contaminated by debris or moisture, then shifting may become difficult or even impossible.
5. Worn-out Clutch
If the clutch is worn out, you’ll have to replace it. The clutch disc and pressure plate are clutch component systems that can wear over time and require replacement.
If they wear out, this will cause the transmission to slip, lose power, and make it difficult to shift gears. Sometimes, a worn-out clutch could result in a situation where your car shakes in reverse.
We advise that you check your owner’s manual for recommended intervals at which to have your car serviced by a mechanic.
6. Shift Lock
Shift lock is a safety feature that prevents the transmission from moving into gear while the vehicle is in park mode. The shift lock can be disengaged by pressing the brake pedal, allowing you to move out of the park mode and engage drive or reverse. If your car’s transmission will not engage any gear and the shift lock is engaged, it may be due to one of two things:
Either the electric motor responsible for engaging/disengaging the shift lock has failed or something else that could prevent shifting into gear has been damaged.
7. Bad Transmission Control Unit
The Transmission Control Unit or TCM is the main computer that controls the transmission. If it has failed and needs to be replaced, your vehicle’s electronic control system may not work.
The TCM must be programmed to work with your vehicle and can be reprogrammed by a mechanic or you can do it yourself. These components are only found in automatic transmissions.
How To Fix Transmission Engaging Problems
1. Transmission Fluid
To check the transmission fluid, you’ll need to lift the hood and locate the dipstick attached to the underside of your car’s engine. After removing the dipstick, wipe off any dirt or debris on it (you don’t want this getting into your engine). Then insert it into its receptacle and pull it out again with a quick movement.
Check both sides of where you inserted it because they may be different colors! If it is minimal or no fluid present, fill up with new transmission fluid as directed by your owner’s manual or local mechanic. If there’s a lot of residual oil present, drain some out using a pan underneath your car.
When refilling, use only manufacturer-specified levels for both automatic and manual transmissions—different cars require different amounts. It’s also important that you do not pour in too much transmission fluid to avoid further issues.
2. Fix Worn Clutch Issues
To fix worn clutch issues, you need to replace the worn-out car clutch. For this purpose, first, raise the front part of the car by using a jack. Then remove the transaxle to get better access to replace or repair your worn-out car clutch.
To get access to your worn-out car clutch, you will have to disconnect all electrical connections and speedometer cables. Disconnect and remove the starter motor so that it can be removed easily later on during the replacement process or repair project.
Remove the drive axle and prop shaft so that they can be reinstalled later in their original position after completing the replacement project or repairing job on your worn-out car clutch system.
Remove the flywheel and clutch disc so that they can be reinstalled later on during the replacement project or repair job on your worn-out car clutch system. Inspect and clean thoroughly before replacing the clutch. After, you are done, put everything back in reverse order.
3. Connect Broken or Dislodged Transmission Linkage
This can be one of the reasons why your transmission will not engage in any gear in the first place. If your linkage is broken or dislodged, you will need to reconnect it before the transmission can be shifted into gear.
This is a very simple process that can be done with no tools. Simply disconnect the transmission linkage from its mounting points, then reconnect it by pushing or pulling it back into place.
4. Replace the Defective Torque Converter
If your transmission is having problems shifting, it’s possible that the torque converter needs to be replaced. The process of replacing a torque converter is not difficult and can be done in your garage if you have the right tools and a little bit of patience.
First, you will need to drain the transmission fluid from the torque converter. This can be accomplished by removing the fill plug on the side of your transmission, then pouring out the old fluid and replacing it with new.
Next, remove all of the bolts holding in place the torque converter in and slide it out of its mountings using a screwdriver or socket wrench.
Clean off any dirt or debris that may have accumulated inside before installing a new one.
Once this is done, install the new torque converter and secure it in place with new bolts. Next, you will need to refill the transmission with fresh fluid by removing the drain plug on your pan once again and pouring in enough to fill it up completely.
You’ll also have to check your transmission fluid level every now and then over time to make sure that it does not drop below the minimum mark on your dipstick.
5. Replace Faulty TCM
Replacing the TCM is a fairly straightforward procedure. You’ll need to remove the transmission pan and then remove the old one. Next, clean out any debris from both sides of the transmission case before replacing it with a new one.
Finally, put everything back together in reverse order so you can test drive and see if your car is fixed.
There are only a few reasons why your car’s transmission is not engaging any gear; bad transmission control, worn-out clutch, unit, shift lock, internal issues with your transmission, bad torque converter solenoid, broken or damaged wiring, or transmission fluid.
If you have the proper tools and knowledge about your car, then you’ll be able to fix transmission-engaging problems with ease. The key is doing your research before starting any work on your vehicle.
If you do not know what each part does, then do some research first so that when it comes time for replacement or repair; everything goes smoothly.
Ugo is a passionate car enthusiast with a Bachelor of Electrical and Electronics Engineering degree and hands-on experience in troubleshooting and fixing automobiles.
I combine my electrical and mechanical engineering knowledge with practical skills to address car-related issues.
My love for cars and dedication to educating others led to the creation of Fixandtroubleshoot.com!