Modern automatic transmissions use pressurized hydraulic fluid to change gears. Every time a gear change is required, the car’s computer activates a transmission solenoid, which directs transmission fluid into the valve body to engage the correct gear. If one of these electro-mechanical valves fail, then all sorts of transmission problems can ensue. So let’s take a closer look at the shift solenoid, and the common problems associated with it.
What Transmission Do I Have?
How Does a Transmission Solenoid Work?
As you’re going down the road, the car’s computer analyzes data being sent by vehicle speed sensors and engine speed sensors. Based on this information, the Engine Control Unit (ECU), or the Transmission Control Unit (TCM), executes the appropriate upshift / downshift by sending a signal to one of several shift solenoids. These transmission solenoids have a spring-loaded plunger inside, which are wrapped with wire. When this coil of wire receives an electrical charge from the TCM / ECU, it causes the plunger to open, allowing transmission fluid to flow into the valve body and pressurize the desired clutches and bands. When this happens, the transmission changes gears and you continue down the road.
The car’s computer can control the transmission solenoid in several ways. If the vehicle is equipped with a dedicated Transmission Control Unit, it can open or close the hydraulic circuit using a direct 12v signal. Or, the Engine Control Unit can control the solenoid’s plunger by turning the ground circuit on and off. A solenoid can be used to control a single gear or multiple gears, depending upon the complexity of the design.
Symptoms of a Transmission Solenoid Problem
A transmission solenoid can fail due to electrical issues, or dirty fluid that’s caused the shift solenoid to become stuck open / closed. Any change in the transmission fluid pressure can cause numerous problems, including:
Erratic Shifting – If you’re dealing with a failed transmission solenoid, the gearbox can skip a gear up or down, shift back and forth between gears repeatedly, or get stuck in a gear and refuse to shift.
Transmission Won’t Downshift – If the transmission will not downshift, one of the shift solenoids may have become stuck open / closed, preventing fluid from entering the transmission valve body to pressurize the correct gear.
Severe Shifting Delay / Stuck in Neutral – In order for an electronically controlled automatic transmission to shift gears, the solenoid must be able to regulate the fluid pressure to activate the appropriate gear. If the shift solenoid is receiving too much or too little electric current, or dirty transmission fluid has caused it to become stuck open / closed, gear engagement maybe become difficult or delayed, which can cause the transmission to act as if it is temporarily locked in neutral.
Because the solenoids are connected to a vehicle’s electrical system, the ECU will usually register an error code and trigger the check engine light if something goes wrong. If this happens, the transmission can go into limp / fail mode, where it will only engage second / third gear to limit the vehicle speed without immobilizing it.
The first thing that your mechanic should look at are the error codes. Using a scan tool, the technician can determine the source of the solenoid’s problem. It could be as simple as a bad ground, or as complex as a failed solenoid pack (a grouping of individual shift solenoids).
Transmission Solenoid Replacement Cost – Parts & Labor
In most cases, solenoids are located inside of the oil pan, connected to the valve body. Depending on what you drive, the technician may be able to replace just the failed shift solenoid. However in some cases, the solenoids come in these multiple unit packs so if there is a problem with one, the entire pack must be replaced. This job typically takes 2-4 hours to complete, and shop time is generally billed at $60 – $100 per hour. The average total cost to diagnose and replace one ranges between $150 and $400.
Depending on the make and model of your vehicle, expect to pay between $15 – $100 for a single transmission shift solenoid. A pack can cost $50 to $300.
| Type | Cost Range |
|---|---|
| Single | $15 to $100 |
| Pack | $50 to $300 |
| Labor | $120 to $400 |
| Total (Pack) | $250 to $600 |
Although it isn’t unusual for transmission shift solenoids to wear out over time, you can extend their life by changing your transmission fluid at the factory recommended intervals. This will clean out all of the dirt and sludge that builds up, and the fresh fluid will keep the plungers on the inside of the solenoids from sticking. If you don’t know what your vehicle’s recommended transmission service intervals are, check the back of your owner’s manual, or simply ask Google.
Get a great deal on a replacement solenoid – for as low as $11 on Amazon <
Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.
What Transmission Do I Have?
Mph needle goes up from time to time even when I’m at a stop and sometimes while I’m driving it gives a kick
Problems shifting on freeway it coded solenoid b electronic
I have a 2002 Buick Park Avenue 132000 miles on it, the trans mission works fine in 1St 2nd and overdrive, the problem is in 3rd gear from 40 to 60 miles per hour I can only explain that it flutters or has a slight vibration until it shifts to overdrive. No computer codes listed.
Would changing the electronic pack in the transmission fix this problem or is a transmission rebuild required?
My car goes in 1,2&3 it jerks I drove it my cousin house at the stop sign it took it a while to go had to shift gears 3 times
Hi I have a 2000 Chevy Silverado 1500 ls 2nd automatic and while I’m in drive the rpms are hi when I hit about 60Km hr to 100 km hr seems like it not shifting gear seems like it it won’t shift to overdrive I changed silonoid b all ready gonna try changing out a as well but if that don’t work what can be my problem
i have a1999 escort it shifts fine into rev and first and second but wont shift into third nice little car if i can get this fixed
If only I knew two weeks ago what I know right now… I figured it out, but a bit too late. I’ve never had tranny trouble and it didn’t seem like this was gonna be my first until it was too late. So, I haven’t had the codes scanned yet, but that’s okay. My question is not “…how do I fix?” No laughing either boys . This chick let some boys do their thing for about 8 months until now and it died anyway. I’m still learning, bit none of this stuff made any sense at all. My truck ended up going into limp mode a couple weeks ago. I kept wondering wtf is going on, and then survival mode…and a dead truck. Well, I can’t hurt it any more but I still would like to know this… If a vehicle has multiple “organ failures” (haha) like my story, and the codes tell me what tripped the sensors, is it going to be fixable…or that stuff leading up to it just made my problem something akin to a metastasized malignancy and they can’t operate? Give it to me straight. I can take it. Will this just be an autopsy so i can know what killed it, (and teaches me so it doesn’t happen again, or isit gonna be fixable? Thanks guys! 😉
I have a 2010 chevy cobalt & thecodes that pull up r P0700 (tcm) P0751(shift solenoid A stuck on) P0752 ( shift solenoid A stuck off) what do u think this could b? & How can I replace the Shift solenoid myself?
1999 f 150, won’t go in to for Word gear in less you rev it up a little then it’s fine till you put it in park. Them you have to repeat what I just said to get it moving again..
i have 2010 nissan navara and the 4-5 and 6th gears are not working,i drive on only the 1-2 and third speed.any help on what to do ? Thanks.
2007 corvette, with only 14,000 miles. AT is stuck in Park. I need to replace the BTSI solenoid. I have the console cover removed, but the solenoid seems to be riveted in on one end and I can’t figure out how to remove the other end where the shaft connects.
I have a 1996 Ford Taurus Wagon. The transmission, in Drive makes a high-pitched whine. It actually will operate in drive but after a few blocks, I generally shift in to “1.”
The car will drive in “1” and in Reverse. Actually, it’s been that way for about 3 years. I live in a small town and used the wagon to transfer things to our storage unit after my mother-in-law passed away. Of course, it only goes about 10-15 mph.
Lately I notice if I shift into 1 from park and the radio is on, it goes off — at least temporarily. When this first happened, I was near a car repair place and the guys there fixed it. Lasted about 2 days. Then it all happened again. They said that whatever they did “could be done once, but not twice.” No specifics.
I have a 2009 Chevy Traverse. It just had both catalytic convertors replaced. Yesterday it broke down after not being able to go over 20 mph. The transmission was rebuilt 3 years ago. Any suggestions
I just want to tell you guys how nice are you to give this information
thank you.
My 2007 Ford F150 have Leaking Fluid from the Automatic Transmission Extension Housing Seal, after packing it for a Mount I drive it to technical and I notice that the movement is very slowly manage to get their for replacement of the extension housing seal, after the fluid was top up with 5 litter. Now it can only drive reveals gear only no driving front gear, please what is the possible solution.
I have a hard shift when taking off when the first thump go past the vehicle runs fine it 05 ford expedition Eddie Bauer can it be shift solenoid?
I have 2004 Toyota c roller auto zone checked it out on their machine it said touqecovter cellouard clucth was either stuck open or closed I read all ur input about what that part does if it is not working rite my car does none of that but sometimes it gets stuck in park n car won’t start unless I twist string whe’ll back n forth plz help ali
took a 100 mile trip. Upon arriving my service engine light came on, It stayed on the return trip, went off when I got home. A couple days later I noticed the car would not go from 2nd gear to third or fourth. I have a 1998 Chevy Blazer. We considered changing the solenoid Will this take care of the problem. We have changed the tranny fluid and filter. It was not dirty and had no shavings in the pan. Advise please..
Have a Jetta 4 1.6. juss fixed the trans recently after it was failing to drive. Now it can drive but no reverse now. I put a 5 litre oil which I bought from the shop. I hear about solenoids and I don’t what to do.
i have a 2000 Golf and the trans stopped shifting into 4th gear (it is a 4 spd auto trans)the solenoid at the 5th position is worn on the bottom side wwere it fits into the valve body, the spot is perfectly round and about the size of a pencil eraser. Any ideas, help me repair the trans please. Thanks
I have a Chevy hhr 2007 first gear don’t work people are charging me 1400 to fix because they say is the trasmition and some other people are telling me this tipe of car have a sensor just to at oil is that true.please help..