My transmission will not engage why?

Most likely this is a failed pump and possibly a torque converter as well.

This is not uncommon on these units when they fail so I am attaching the process on how to remove and replace the transmission and converter.

Here is a video that will help with this:

https://www.youtube.com/watch?v=ZC7xHVMKLRw

https://www.youtube.com/watch?v=3vJAojsrfuU

Please review the material below and let us know if you have questions. Thanks

Hello,
I have a Grand Caravan. At around sixty five mph the transmission completely disengaged. Pulled over, shut the ignition off and reset the computer and it would drive and then disengage again. Before it would disengage, it seems to be shifting. Also, no reverse.

After doing some line pressure tests and code scan I have a P0882 and P0732. It failed the following test as per service manual. But being there is no reverse at all, I am not sold on a solenoid or TCM fault, because based upon pressure gauge responses when shifting. However, In limp mode as per the manual, I should have park, neutral, reverse and second gear.No reverse I am stumped.

Test two a-selector in overdrive (fourth gear):
1. Attach gauge to the underdrive clutch tap.
2. Move selector lever
to the (overdrive) position.
3. Allow wheels to rotate freely and increase throttle
opening to achieve an indicated speed of forty mph.
4. Underdrive clutch pressure shoul
d read below 5 psi. If not, then either the solenoid assembly or
PCM/TCM is at fault.

Reverse is not solenoid controlled, it is mechanical through the manual valve. In reverse the L/R clutch and the reverse clutch applies. Its loss suggests that some splines stripped on the shaft or the drum cracked.

Either way the transmission would need to come apart to repair it.

Thank you... I was pretty sure of that, but with the combination of the distracting signals and the manual not stating exactly what you stated (mechanical through the manual valve). I did not want to condemn the transmission immediately. One last question, if it is not solenoid controlled, would it not have loss of forward in the L position as well as the R position for the L/R clutch?
I removed the EATX relay to induce a limp mode and do not have any forward or reverse. When I put the relay back in, I have forward gears. I appreciate your response very much!

Sounds like you have two failures. Both a bad L/R solenoid and failed reverse clutch. When power is removed all the solenoids should go to default position. That should give you Park, Neutral, Reverse, and Second gear on the manual selector. If the L/R solenoid is stuck partly open you would lose reverse with the power cut. The flow diagram is reverse S4 is the L/R solenoid.

I appreciate all your help..., thank you! Looks like I need a Tranny! Thanks again!

Not sure I should be thanked for that.....

Thank you for using 2CarPros.com Come back with any automotive questions.

No gears at all. Driving and lost forward motion. Coasted to stop. Park works but no forward or reverse not even limp mode. Fluid is up and red, rpm's go up a bit when selecting reverse and drive. No bad noises. CV joints good. It is like it is not getting a signal to go into gear. What could cause that? Should it have not gone into limp mode if a clutch pack went bad or a solenoid got stuck? I pulled the cooling line and started it up, fluid squirted all over so pump must be good. I dropped the pan and very little fine shavings on the pan magnet. What to look for?

Based on the symptoms you described for your 2005 Dodge Caravan, where there is no forward or reverse gear engagement and no limp mode, it suggests a potential issue with the transmission system. Here are a few possibilities to consider:

Transmission Control Module (TCM) or Solenoid Issues: The TCM controls the operation of the transmission, including the activation of solenoids that engage the gears. If there is a malfunction or failure in the TCM or a specific solenoid, it can result in a loss of gear engagement. It's worth checking for any error codes stored in the TCM using a diagnostic scanner to narrow down the specific issue.

Internal Transmission Failure: While you mentioned there were no bad noises and the fluid appeared normal, there is still a possibility of internal transmission damage or failure. This could include issues with clutch packs, planetary gears, or other components. The presence of fine shavings on the pan magnet could indicate normal wear, but further inspection and potentially a teardown of the transmission may be necessary to identify any significant problems.

Mechanical Linkage or Shift Cable: Check the mechanical linkage or shift cable that connects the gear selector to the transmission. If it is damaged, misaligned, or disconnected, it can prevent the transmission from shifting into the proper gears.

With the van up on jacks, I can rotate one wheel and the other rotates the opposite direction as it should. no odd noises.
If it is the final drive, would the transmission it self go into gear?

Also, to eliminate an electrical issue, if I disconnect all electric to and from this transmission, will it go into limp mode or do anything at all?

if the final drive was faulty, the transmission should still go into gear,the out put shaft may have broken, it really sounds as if the transmission needs to come out and be inspected.

I was afraid of that. Sure was hoping to find the cure without having to do that.

yes, i do understand, but with what you are reporting, it does sound as if it is an internal failure, as you have line pressure (pressure not known but you have flow) no codes and the diff looks as if it sound, i probable would be looking at getting a scanner with live data, with this hooked up you can actually watch the solenoid's turn on and off, this will prove electrical connections are ok as well.

The transmission down shifted and then mad a clunking noise. I pulled over
and it seamed to go into park but shifter was in drive. When it would not
change to neutral when stopped, so I could push it off the road. I had to jack
it up and play with the wheel and shifter to get it to move. I had a wrecker
take it to the house .now when you put it in gear it it will jump ahead but never move when accelerate. What could be the problem?

It sounds like you have a broken drive axle. Here is what I want you to do. Using a flashlight have someone get into the car and put it in drive. You carefully look under the car with the flashlight to see if either axle is turning. I have seen an axle break right at the outer CV joint in which case the car will not move and have the problem you are describing.

Please let us know what you find. I'm interested to see what it is.

Cheers, Ken

Car is hard to run in the morning, gears not engaging but only after a lot of gas is given, then moved with this same with reverse despite heating, moves noisily banging sound after more gas is given, have to do so several times in drive way to an fro. After running while runs okay all day.

Good morning,

It sounds like you may have a clogged filter in the transmission pan.

https://www.2carpros.com/articles/automatic-transmission-problems

I would start with changing the oil/filter in the transmission. beyond that it will be an internal failure such as seals that are hard from over time.

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Roy

Thanks, I will let you know.

Sounds good.

Roy

My van won't go forward or in reverse unless there's a click, you have to wait for it and the it will move. All the warning lights are on and it shows reverse when it's in park. I changed the filter and put new tranny fluid in it and it moves but I don't know what this all means. Thank you for any help you can give me.

Hi,

Can you tell approx where the click is coming from? Also, the idea that it shows reverse when it is in park may indicate the shift linkage needs to be adjusted. That is where I would recommend starting.

If you look at the two pics below, they include the directions and pic for adjusting the shift cable. Try this first.

Next, when you say all lights are on, are you referring to the warning lights such as the check engine light? If so, have you had the computer scanned for diagnostic trouble codes?

If you haven't, that will need to be done as well. Here is a video showing how it's done:

https://youtu.be/InIlnsjOVFA

I realize most people don't own a scanner, but oftentimes a parts store will lend you one.

Try the adjustment first and let me know what you find.

Take care,

Joe

See pics below.

Thanks bro, I changed the filter and transmission fluid, lots of metal shavings on the magnet, cleaned it all up goes good shifts down hard, running a little rough checked the plugs and wiring. I think it could use a tune-up up, drive it until it goes or blows. I don't think the fans are kicking in, next on my list. Thanks for answering, paid $400.00 for it if nothing else it can sit in my yard. Man Van. Got an 81 Citation with the Iron Horse motor. I'm a sucker for crap! Stay Safe.

Hi,

I'm glad to hear it is working again. The old iron duke. Great engine. I had a 81 Citation with the same engine years ago. It never said no. LOL Always ran.

Take care and feel free to come back anytime in the future if you have questions.

Take care,

Joe

Will not back up will go in forward.

We need to start with checking fluid. If it is low it could cause issues but it is unlikely that this would only effect reverse.

The most likely cause is the valve body has a leak in the L/R solenoid which is allowing fluid to leak past a point that is supposed to be blocked off which would create the needed pressure. Unfortunately the only way to repair this is to replace it or rebuild it.

Let me know if you have questions and we can go from there. Thanks

https://www.2carpros.com/articles/automatic-transmission-problems

Okay, i do not have to push the brake to shift from park. But that is not the question. It will not go forward or backwards its like the brakes are locked down and it just bogs the motor soon as i out in reverse or drive. It doesn't shut off just pulls the motor down some. But it will not move.

Good morning,

This sounds like you have a torque converter failure. It is locked up and when this happens, it gives you the symptoms you currently have.

https://www.2carpros.com/articles/automatic-transmission-problems

I would have someone check it for you to confirm.



Roy

Are you sure? that is a lot of work to tear down and replace. Could it be a sensor or module or something?

Can you please shoot a quick video with your phone so we can hear and see the noise? that would be great. You can upload it here with your response.

When I drive the car takes a while to shift into gear and I doulbe check, the water,motor oil, and transmission oil every mornining before leaving so i know its not missing oil. I have notice that every time that i stop and then go it like forces it's self it turn on the (servie engine soon) light. How do i go about trying to fix it or to repair to find out what it is.

Suspect speed sensor and or coil solenoid pack need to have the codes you can have it scanned or cycle the ignition key on off on off on read P0000 codes in the odometer area

When I put the lever to reverse it wont engage,,,so I will put in drive then back to reverse and sometimes it will go into reverse...also my speedometer is at 30mph when I start the van.,once I can get the van to move in either reverse or drive the transmission works fine,shifting like normal.I replace the input and out speed sensors and stil doesn't go into gear like it suppose too.Could my neutral safety switch be bad or is something else the problem,also my backup lights are on as soon as I start the van.

Sounds like the shifter cable is loose, stretched, or misadjusted. I'd start by watching the lever on the transmission to see if it clicks solidly into each position while a helper works the shift lever inside.

You can also use a Chrysler DRB3 scanner to view the gear selected and see if that agrees with the shift lever's position. A lot of independent repair shops bought DRB3s, so you might ask around at some local shops to see if you can find one. You'll find them at any Chrysler dealership too.

Shifter linkage is moving ok,but now my speedometer doesn't work and it wont go out of low gear...

Staying in second gear is "limp mode" to allow you to drive slowly to a repair shop without needing a tow truck. The diagnostic fault codes need to be read and recorded to know where to start the diagnosis.

my codes are po700 po715 po720 p1899....I have put in new input speed and output speed sensors.I was told it was my neutral safety switch,but my van doesn't start in any other gear except park and neutral could the transmission control solenoid be what is causing all my problems

P0715 - Input/Turbine Speed Sensor Circuit Malfunction
P0720 - Output Speed Sensor Circuit Malfunction
P1899 - Park/Neutral Position Switch Stuck In Park or In Gear

You have fault codes directing you to the circuits that need to be diagnosed. Don't go looking for other unrelated stuff. The first concern is it is very unlikely you have three sensors that failed at the same time. Instead, look for what they have in common. In this case that is the wiring harness. The second thing to be aware of is the neutral safety switch is no longer the inexpensive, reliable switch that worked fine for many decades. It is a "range sensor". This one has five separate switches in it that turn on and off at different times. Those must agree with the short list of acceptable combinations. When any one of them does not go to the correct state, code P1899 will set.

Any one of these three codes will send the system into limp mode. Inspect the wiring harnesses first for signs of wires rubbed through, then for corrosion on connector terminals. The next step would be to use a scanner to view live data and see if either speed sensor is generating a signal. Also look at the Transmission Range Sensor to see how it is listed. I have a Chrysler DRB3 scanner for all of my vehicles. That shows the gear that is selected as interpreted by the Transmission Computer. You may be able to get an idea as to the cause of the problem by watching how it acts while moving the shift lever. If an incorrect gear reading only occurs when shifting between forward and reverse, with the engine running, for example, a good suspect is something related to a wiring harness that is flexing when the engine rocks. If the problem shows up when the engine is not running, an intermittent contact inside the range sensor becomes a better suspect. A problem in the range sensor could act up every time you shift to a certain gear, but it is usually the only suspect when the incorrect readings show up intermittently as you shift back and forth.

thank you for the advice...I will check all connection and will let you know if my problem is fixed

I checked all the connections and found a connection was corroded and replaced it.I also have po700 po715 po720 codes,i replaced the input and output sensors.My speedometer doesn't work ,but the other gauges are working.The transmission is still not shifting it is still stuck in one gear and when I put it in drive and back to park my indicator still shows its in drive until I move to drive then back to park.

The next step is to use a scanner to see what the Transmission Computer is seeing. If the range sensor is not reporting the correct gear you have selected, that sensor becomes suspect. Most scanners will also let you test the individual switches in that sensor.