Hi there,

I just have my transmission light on and off for several days now.

when i first start it, it will light up and on few occasions i just turn the engine off and back on again and it will go away.,

drive it for a few minutes, then will light back again, restart again and it will go away.

drive it around for about 15 to 20 minutes and it drives okay.

following day, its the same thing again.

what should be the first thing i need to check if its an electrical issue.

btw, i am not using this car daily hence i keep the battery connection off both negative and positive.

i only connect it if i need to drive around the block.

i have a 1994 xj6 vanden plas with vin 666459

mileage just hit 188,888 miles just today.

your help is very much appreciated.

 

Hi kcidmad:

The transmission light is on, but the car has not gone into 'limp mode'. Is that correct? I.e., besides the light the car drives normally?

Scott

 

Hi kcidmad,

Scott's question is a very good one and we'll be anxious to hear your answer.

In the meantime, the first thing I would suggest is that you check the electrical connector for the Throttle Position Sensor (TPS). This connector clips to a bracket mounted on the intake manifold a little left of the throttle body. Carefully pull out a slim plastic tab and the connector will slip off the metal bracket. Then carefully disconnect the two halves of the connector and inspect for oil or other contamination.

Flush out both halves with zero-residue electrical contact cleaner spray and let them dry. Wipe the outside of the smaller/inner half of the connector with dielectric grease to help seal out future gunk, reassemble and see if the transmission light issue goes away.

If your answer to Scott's question is that yes, when the trans light is on the transmission locks in 3rd gear, which is known as "Limp Home Mode," then I would be even more suspicious of contamination of the TPS connector.

Try cleaning the connector, let us know about the Limp Home Mode, and we'll go from there.

Cheers,

Don

 

I would be interested in the possible solutions others may offer as well.

Our red car will start and up shift normally,even with my talented foot glued to the floor,5 grand shifts all the way to stupid speed.

But rolling down the road,put my foot down and it will not downshift at all until I hit the floor button,then "poof",it will mis-shift,then light on and third gear treatment until I shut the car off and restart.

It will downshift fine when done manually.
I will be checking the easy stuff first,throttle position switch,servicing the fluid,etc.

No codes on the vcm either.

Ideas anyone?

Jim

 

Hi Scott,

thanks for your reply, yes the transmission light is on but it is not in "Limp mode" but i notice that there is wrong on how it shift.

the speed is slow when the transmission light is on and i think it only goes to 3rd gear.

thanks.

 

kcidmad:

Hmmm… That sounds to my ears like you car HAS gone into "limp mode." It would feel very slow and unable to shift past 3rd. Please read Don's post carefully. The TPS is widely known as the culprit for such things. Don's initial recommendation is to inspect and clean the connector. IF the TPS itself is to be adjusted, cleaned, or replaced be very careful about disturbing it's position. It must be precisely calibrated for accurate shifting to occur. Does all that make sense? Here's a link to the tranny check list from Jag-Lovers that is also located in our "sticky" section.

Jag-lovers' Ebooks

Scott

 

Jim:
Keep in mind, I'm NO expert… But I'm wondering if a dirty TPS might also cause the condition you are describing. At least, that's the first thing I'd look into if I were you. There is stuff posted in the archives here and elsewhere about guys drilling small holes on the top and bottom of the TPS (since I've not needed - yet - to do it, I can only imagine required taking off the throttle body to accomplish) in order to occasionally spray with electrical cleaner. A lot of grime gets built up there over the years and seeps down into the TPS.

Scott

 

Thanks for the affirmation of my suspicions about that sensor Scott.I am gonna try to wake Redd up this weekend.

Before I parked it last fall,on last start it idled at 1500 rpm and would not settle down as well.

Just another one of the little see-too's before spring time fun

 

Scott,

You're exactly right that the TPS itself may be contaminated and that may be the cause of the Limp Home Mode, but since a contaminated electrical connector has been the cause of every one of our LHMs except one (cold solder joint in the TCM), my suggestion was to clean the connector first, since it's really easy to do and nothing needs to be removed. Cleaning the TPS would be one of the next steps I would advise if cleaning the connector doesn't solve the problem. Other steps would be to follow the Jag-Lovers eBook diagnostic procedure, and along the way to service the rotary switch, transmission electrical connector, decoder module, and TCM.

To clean the TPS, you don't necessarily need or want to remove it from the throttle body, but you do need to remove the throttle body from the intake manifold. That's not difficult, just involved. Below are links to photos of that process, as well as drilling drain holes in "corners" of the plastic case of the TPS to allow flushing it with electrical contact cleaner spray.

Cheers,

Don

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page

 

Below are links to the other transmission service issues I referenced in my previous post. See why I didn't mention all this in my first post?

But since you asked, here they are:

Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page
Welcome to Jag-lovers - Members Photo Viewing Page


Cheers,

Don

 

For some reason the link above to the photo album about drilling drain holes in the TPS isn't working, so I'm trying again.


Welcome to Jag-lovers - Members Photo Viewing Page