Transmissions

Have Transmission Questions? Ask a Mechanic for Answers ASAP

Ask an Expert,
Get an Answer ASAP!

I am trying to diagnose why My O/D off and Trans Temp lights…

Customer Question
I am trying to diagnose...
I am trying to diagnose why My O/D off and Trans Temp lights come on but trans does not feel warm. I have replaced the governor pressure sensor/trans oil temp sensor. I don't think I have a wiring problem, the temp sensor resistance is the same @ the connection at the trans housing and at the PCM. I'm sure I could replace it with a solid resistor to allow overdrive to function but I'd like to determine what temperature the computer is seeing (based on the voltage on the temp sensor circuit) and see if it's actually too warm somehow or if this is related to another problem
Submitted: 2 years ago.Category: Transmissions
Show More
Show Less
Ask Your Own Transmissions Question
Answered in 8 hours by:
2/23/2016
Transmission Mechanic: sprinkles08, ASE Certified Technician replied 2 years ago
sprinkles08
sprinkles08, ASE Certified Technician
Category: Transmissions
Satisfied Customers: 24,232
Experience: Chrysler/Dodge/Jeep master tech ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans Specialist
Verified

Hello and welcome to JustAnswer!

Either it's seeing an incorrectly high temperature signal or the trans is actually overheating. It wasn't uncommon for the drainback valve to stick closed or the cooler to become restricted and cause actual overheating, but this would happen after driving long enough for it to actually overheat. If the problem happens shortly after starting and actual overheat isn't possible yet then it's going to be an electrical issue. If if it's an electrical issue then it's either the sensor or wiring.

Have you checked for fault codes?

Ask Your Own Transmissions Question
Customer reply replied 2 years ago
There are no trouble codes. I don't think it's a sensor as I have already replaced it with no change. I don't think it's wiring between the sensor and the pcm as the values measure the same. At the moment the O/D off first illuminates I measure a voltage drop of 2.57V across pin 1 connector A (trans temp sensor) and pin 4 connector B (sensor ground) at the pcm. I would think this is well within range of a typical 5v signal, resistance across the sensor is 2010 ohms. I'm wondering if there is a chart which shows the range of acceptable sensor readings and the temperatures that correspond to them?
Transmission Mechanic: sprinkles08, ASE Certified Technician replied 2 years ago

There isn't a chart that shows resistance versus temperature as a scan tool is used to diagnose the system.

If the trans isn't actually overheating then you have a wiring or sensor issue. It's either actually overheating or an incorrect temperature signal is causing the PCM to think it's overheating when temperature is actually ok.

Does trans temp show the same as ambient and coolant temperature after a cold soak?

What does it show when the lights come on?

Has temperature been checked at the pressure line leaving the trans using an infrared thermometer while the lights are on?

Ask Your Own Transmissions Question
Customer reply replied 2 years ago
i have not had access to a scan tool that will read the trans temp, i also do not have an infrared thermometer. still waiting until a friend with these tools makes it over to help. the trans pan is never hot to the touch. since the voltage / resistance is the same at the trans and at the pcm, that wiring is not causing the problem. I replaced the sensor ^^ and no change. I have no dtc set. I did some research and see that the sensor should have approx. 1000 ohms resistance at room temp. The new one has 1.6k. thats pretty close right? I can't imagine that there is no documentation regarding the trans temp system operation ex: '@ 3.0 v o/d is locked out, @ 3.4v trans temp light illuminated. I see a range of 1.55 to 3.76v based on when high and low signal DTCs should set. my voltage is always in the low-mid 2's Based on this I believe the pcm Is receiving a good signal. I swapped the pcm and no change. I then figured there could be an issue with the cluster, swapped that out and no change. At this point I think there must be a wiring problem somewhere else but I don't know where to look
Customer reply replied 2 years ago
the dash reads 'no bus' in the odometer display and abs light is on, not sure if either of those things could be related but figured i'd mention it.
Transmission Mechanic: sprinkles08, ASE Certified Technician replied 2 years ago

Does the problem only happen after driving for an extended period or will the trans temp light come on shortly after a cold start?

Ask Your Own Transmissions Question
Customer reply replied 2 years ago
After a*****or 15-20 minutes not driving. When o/d off comes on trans tempt will be on within about a minute. Once they comes on I have to let it sit for probably 6 hours or more for them to not be on when I turn the key on
Transmission Mechanic: sprinkles08, ASE Certified Technician replied 2 years ago

Has the cooler been flow tested? If so what were the results?

Ask Your Own Transmissions Question
Customer reply replied 2 years ago
Cooler flow has not been tested, is there a DIY procedure for that or should I just point the return hose at a bucket, start it in neutral, and see if fluid comes out?
Transmission Mechanic: sprinkles08, ASE Certified Technician replied 2 years ago

Drive it until it's indicating overheat. With the vehicle properly supported and the return line ran into a container, start the engine and measure the amount of return flow for sixty seconds in neutral.

Ask Your Own Transmissions Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a transmission mechanicLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask sprinkles08 Your Own Question
sprinkles08
sprinkles08
sprinkles08, ASE Certified Technician
Category: Transmissions
Satisfied Customers: 24,232
24,232 Satisfied Customers
Experience: Chrysler/Dodge/Jeep master tech ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans Specialist

sprinkles08 is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry.

Stephanie PElm City, NC

used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future.

David L.Richmond, TX

9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much.

PhilMarysville, CA

Lurch. Thank you very much. I had real doubts about this website but your promptness of response, quick followup and to the point answer with picture was incredible.

CharlesWalnut Creek, CA

As a single woman, I really appreciate an excellent and affordable opinion.
Thank you Geordie, I will not hesitate to contact justanswer in the future!

SueCharleston, WV

Another great insight to what may be the problem. I will have my mechanic take a look at it tomorrow. Thanks again, Frank...you do indeed know your stuff.

JimCastleberry, FL

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

< Previous | Next >

Meet the Experts:

Chris (aka- Moose)

Chris (aka- Moose)

Technician

1,918 satisfied customers

16 yrs. experience with auto, manual, & CVT drivelines

Tim&#039;s Auto Repair

Tim's Auto Repair

Mechanic

507 satisfied customers

I have been rebuilding automatic transmissions for 25 years

Gary

Gary

ASE Certified Technician

407 satisfied customers

25 years GM master tech

Matt

Matt

Engineer

152 satisfied customers

Mechanical Engineer BEng Hons22 years experience in car engine industry, 10 years in formula 1

Mike Kelly

Mike Kelly

ASE Certified Technician

150 satisfied customers

17 years experience as an auto mechanic, foreign and domestic. 5 years running my own repair business.

Dave Nova

Dave Nova

ASE Certified Tech

98 satisfied customers

ASE Master Certification. 25 yrs experience

John Mc

John Mc

Trans specialist

93 satisfied customers

Transmission dealer tech for over 19 years

< Previous | Next >

Related Transmissions Questions
I have a 2001 Jeep Grand Cherokee with a 4 liter 6 cylinder
I have a 2001 Jeep Grand Cherokee with a 4 liter 6 cylinder it does not shift up or down I replaced the governor speed sensor and the transponder right next to it change transmission fluid and filter … read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
2007 toy rav4 code in the ecm: P0712 trans temp sensor A
2007 toy rav4 code in the ecm: P0712 trans temp sensor A circ low input. The transmission also did not shift correctly. Common cause?… read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
I have a 2007 dodge ram 3500 i have a p1740 code some times
i have a 2007 dodge ram 3500 i have a p1740 code some times when you are at 3/4 to full throttle bet tween 35 and 45 miles an hour the transmison will go in to neutral as soon, as soon as you let off … read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
I have a 2001 Dodge diesel with a 46 Re: and it will not
I have a 2001 Dodge diesel with a 46 Re: and it will not shift into first or overdrive when it's cold after it warms up I turn it off and restart it everything works great … read more
Reggie Whiddon
Reggie Whiddon
Shop Foreman
Vocational, Technical or Trade School
157 satisfied customers
99 dodge durango 5.2 intermitant trans limp mode 100 miles
99 dodge durango 5.2 intermitant trans limp mode 100 miles to 700 miles have changed all trans selinoids throddle position sensor oxygen sensors cleaned all grounds neutral safty switch mass air senso… read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
I have a 1998(1998.5) dodge ram 2500 5.9l 24 valve 4x4 46re
I have a 1998(1998.5) dodge ram 2500 5.9l 24 valve 4x4 46re or 47re automatic. When you put the truck into drive it goes into 3rd. I can go up to around 50 slowly and it just doesn't want to go into o… read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
I have several codes in my 2006 dodge 3500 P0868 P0713 P0973
I have several codes in my 2006 dodge 3500 P0868 P0713 P0973 P2769 and transmission is in 2nd or 3 rd and won't shift… read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
Dgdge 2500 5.9: the trans over heat ligth came on and the
the trans over heat light came on and the overdrive off light came on I stopped and cooled and they went off but came back on again ?? did not happen before ob2 code P1281 P1740'also PO442 and PO455 e… read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
Tranny starts off high when put into drive, and doesnt shit
Tranny starts off high when put into drive, and doesnt shit down, but shifts just fine when put into low and shifted up into drive. It also makes a whistling noise if you try to push it when put into … read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
transmission will not stay in O/D in and out, after a little
transmission will not stay in O/D in and out, after a little while in will not shift into O/D at all.… read more
fordguy4u
fordguy4u
Automotive Tech
Vocational, Technical or Trade Scho
70 satisfied customers
grand cherokee laredo: 1995 jeep grand cherokee laredo, 6 cylinder,
1995 jeep grand cherokee laredo, 6 cylinder, 42re transmission. overdrive problems. everything was working fine. then o/d off button stopped working. repalced switch. still not working properly. when … read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
i have 07 dodge ram. starts off in 3rd gear, never shifts.
i have 07 dodge ram. starts off in 3rd gear, never shifts. if you pull into 1st it will go but skips 2nd.… read more
sprinkles08
sprinkles08
ASE Certified Technician
High School or GED
24,232 satisfied customers
Grand Cherokee: Jeep, Grand Cherokee 2002 4.0L takes a long
Jeep, Grand Cherokee 2002 4.0L takes a long distance to change gear and sometimes don't change. This I noticed after changing the engine computer: P1763 Governor pressure sensor high P1762 Governor pr… read more
Pete
Pete
Independent Auto Technician
Vocational, Technical or Trade Scho
138 satisfied customers
Transmissions: I got the information and there is much in this
I got the information and there is much in this data. I am using this Tranny with an electric motor for a school project and attempting to make all the gears to work on an electric stand alone test pr… read more
eurotec
eurotec
Vice President / Manager
Associate Degree
11 satisfied customers
Ranger: My 2000 Ranger kicks out of O/D if I exceed 60mph for
My 2000 Ranger kicks out of O/D if I exceed 60mph for more than a minute, when up to temperature.....… read more
Chris (aka- Moose)
Chris (aka- Moose)
Technician
Vocational, Technical or Trade School
1,918 satisfied customers
Dodge Dakota: Hey. I have a 91 dodge dakota with a 318 magnum.
Hey. I have a '91 dodge dakota with a 318 magnum. it has a 3 speed with overdrive. After having some repairs done (front & rear breaks, tierods, couple bushings), the trans won't shift into o/d. Alway… read more
Mike Kelly
Mike Kelly
ASE Certified Technician
Vocational, Technical or Trade Scho
150 satisfied customers
GM: Hi I have just rebuilt my 4l80e and it works sweet first
Hi I have just rebuilt my 4l80e and it works sweet first up while cold but soon as it warms up it hangs slightly on changes and wont go into o/drive. I replaced the force motor, pressure board and bot… read more
Gm Tech (Cam)
Gm Tech (Cam)
Owner/Technician
Vocational, Technical or Trade Scho
6 satisfied customers
toyota soarer: i have a automatic 98 model 1jz-vvti toyota
i have a automatic 98 model 1jz-vvti toyota soarer and the overdrive (4th gear) is not working so it is staying in 3rd gear and has the rpm value of 3400 whilst doing 100km. when the overdrive button … read more
Glenn Bradley
Glenn Bradley
Diagnostic Technician
Vocational, Technical or Trade Scho
18 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x