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?
I have a 03envov harsh shift 1 2 and no reverse
Hey
I have a Chrysler Town and Country 2009.the battery died so I changed it
Then reverse gear caused problems, as well as driving forward motion jammed 3.LAMP computer is on.code: P0733.po734.p0792.p3235.p3041.c1041. A few hours later the car returned to normal also go forwad and revrs.the lamp is still on .
The next day the car again caused problems especially when reversing.
Said the garage should replace Gir.is idea whether anyone can be an electrical problem?
Thanks
Hey
I have a 2009 Chrysler Town Country, after replacing the battery began to appear in my adult problems, gears sometimes get stuck and sometimes reverse Aobrim.hiloc stuck and does not move and sometimes travels Rgil.bmosc said that needs replacing chalk.
LED computer is on and warns of malfunctions: p0733 / p0734 / p0792 / p3235 / p3041 / c1041 /
Anyone know really need to replace chalk? Or that an electrical problem?
Thanks
hi I have a problem with my transmission Pontiac g8 my shifter stucking on park stick but on my screen is drive it is a solenoid problem.
Nader, driving with only 4th gear is only gonna put a stain on the motor and eventually damage the piston and their rings, causing the engine to smoke and be more trouble in the future! Save your motor and fix the tranny; have a shop check it for you, but get a second opinion! Shop around!
i have a 2008 ford escape v6. engine starts, revs, drives forward slightly and reverses a little but then it stops. it will only move about a foot then it stops moving but stays started and will rev if i push on the pedal. it basically moves a about a foot every time i restart the engine
I have this code in my kia rio 2007! What would happen if I ignore this issue and drive my car with one gear (4th gear)
2007 Hummer H3. Problems described above just hit this morning. Reverse is great. Drive for a while and take off from standstill and give gas and engine revs high and has hard time shifting. Shifted to second gear to take off and it did but suffered when got to 3 gear engine rev and could not go any higher than 40 or 30 without worry of engine over revving. Engine light came on. Made it to Dealer and they are saying engine code is transmission. Cannot fully diagnose until Thursday, but possibly a solenoid. I read all of the descriptions and it seems that is the issue…..I truly hope. I would think if it is the actual “transmission” it would make sounds and not shift and it would be a gradual issue with no engine light coming on. Thank you for the information and comments it really helps for understanding how things work.
My ford ranger V6 4.0l doesn’t have enough torque on reverse gear. This follows a sudden bang noise from the engine while the vehicle gear lever was in the reverse mode. I have to put more pressure on the petrol pedal every time to have the vehicle move backward, still at a very low pace! The engine is equipped with an automatic gear box and petrol powered.Please advise on the possible cause of the problem. Thanks…
Simon
My truck is a 97 ford ranger 2.3 and from 1st to 2nd gear when you speed up fast it jerks a bit.
Hi, I have a 2009 Ford FG XR6 Falcon. Bought it second hand from a Toyota dealer. There is an intermittent problem with the 5spd Auto Transmission where it feels like the gears are slipping, generally after going from Reverse to 1st. At slow speeds it can upshift and downshift eratically. Although the dealer couldnt replicate the intermittent Trans issues, they replaced the transmission with a full recon one. 2 weeks later and the Transmission has the same problem back again. Because the issues cant be replicated they can not do anything further. Computer checks have provided no cause and no error / faults are reported. Any advice on what might be causing this would be greatly appreciated.
Changed 1-2 solenoids in my 1993 Toyota corolla Le, also replaced VVS and new filter/fluid. Now I’m still getting the same codes on OBD even after clearing the old codes out. The trans is still surging not wanting to change gears right at times and goes into Limp-mode at times. I’m wondering if the new solenoids (rostra) are just cheap and faulty because what I changed out supposed to had fixed the problems. Any advise would be deeply appreciated .
I’ve had similar issue with my transmission on Mazda 3, 2004 last year. When engine is cold my vehicle drives with no issue, but once it warms up after driving 10-15 minutes gear start shifting from 4 to 3 or from 1 to 3 or 2 to 4 with engine light on. I took my vehicle to mechanic and was told that computer module needs to be replaced which cost around 1500$ plus labor fees. It seems to high to me for the part and cost of repairing for 11 years old car. I decided to do some research and found out from people on forums online that there only Vehicle Speed Sensor ” VSS ” needed to be replaced which was not hard to find the location between engine and transmission. So i purchased the part from online parts store which cost me with shipping around 60$ and took it to different mechanic as i did not have right tools to reach the screws. It took less then half hour to replace the part and clear all codes and engine light. After testing the problem completely gone, i never got any transmission problem and drove my vehicle for another year then trade it to new one. Hope it helps with resolving your issues, but doesn’t cost to much to test.
BTW: I’ve had this issue for 1 year, been driving like that as i could not afford for repair untill did my own resource.
I have a 2008 Chevy Silverado and had my engine lite come on, I ran the codes and 3 came up…..P0573 (cruise control/brake switch Circuit A High), P0787 (shift timing solenoid Low Voltage), P0700 (Transmission Control System Malfunction). I replaced the 3-2 down shift solenoid along with the oil and filter. The light cleared after a couple cycles, but returned about a week later intermittently. Now it stays on, and I am wondering if it could be the wiring harness? It is a job to drain the oil (no plug) and the harness is about $100, do you think it is worth a shot to replace the harness or could it be related to the cruise control vice versa? My only symptom beside the light, is that the truck will not downshift from 3rd to 2nd. Any suggestions would be appreciated.
I have a 1991 Chrysler Town and Country mini van and I was driving it just fine stopped at a stop sign and then went to take off and nothing happens. It will shift into park, neutral, etc but when it’s in gear it will rev up to about 2500 rpm and the same in reverse but in park or neutral it revs all the way up. When I Rev it in reverse and put it back in park it jumps forward. Any help or suggestions would be appreciated
I am a bit confused, I own a 2002 Rav 4 J 4WHD.For the past 6 months it has developed to harsh movement especially at lower.speeds,the car tend to hesitate with no fault code.
The mechanic adviced to.hange the fluid which did not work and then he recommended to change the transmission which I refused.
Last night my colleague who has the same car type borrowed me his ecu and I transfered to my car temporarily.
The car ran smoothly and I comfirmed. While putting back the original ecu it worked fine this time with no symptom of hesitation.
Is anyone understand this synerio?did the errors in the transmission resetted by itself?$
I’ve scrolled through all the problems others have posted and I truly feel for them. My problem is an 02 explorer. I’m driving down the road at about 40mph when without any warning it just quit pulling. Never had any trouble out of it before. It shifts and the linkage moves when I shift but it won’t engage. It shifts real easy with no resistance there was no slippage or noise no gray smoke or any other color for that matter. I’m disabled and can’t afford to buy another vehicle or pay someone to guess the problem. They want $200 just to look at it I only paid $2500 for this one. I could use some feed back.
2001 ford expedition when it hits 30mph tranny goes into neutral and when it drops back down to 25mph goes back into drive no lights come on at all
Changed shift solenoid and torque.ran good for a week and back to same issue..what could cause to go back out in such short time?
My 2003 Chrysler Town and Country is delaying when i put it in reverse. When in drive and stopped at a stop sign. It will sometimes jerk when starting off. Does this sound like a solenoid or a more severe problem
I have a 2002 Pontiac Bonneville, I am thinking I have a bad shift solenoid. My car goes into gear fine, but I feels like it skips second gear all together the car will rev up like its in neutral, then will shift into gear finally and go, after it hits about 30mph. I took it to ammco they quoted me $2800.00 and said they would have to rebuild my tranny! Never said anything about a shift solenoid. Anyone have any thought?? I would be much appreciated