automatic tranny over heat light problem anyone?

[surferboy]

Yup, folks here we go again, just as i thought i'd get a break, i get into my van tonight to go somewere and i noticed after driving for about two minutes that the A/T temp light is on..(botom right hand side of dash board)
so since i never had this problem before i don't want to take any chances and turned around to go back home and phoned hutch in vic which advises me that this is the light for the automatic transmission fluid temp...

he then tells me that its probably coming on cause the tranny is over heating. the van had been sitting in my parking lot for a few hours before i got in to drive it again so how could the tranny over heat so fast? well following is advice, i checked my tranny fluid level with the dip stick while the van was running like he told me to do, and it was between the two notches were the word cold is engraved.. i figured that since the van hadn't been running for awhile that this was probably the right reading so the problem doesn't seem to be from the fact that my tranny fluid is low.. so step two in the trouble-shooting process was to check for this fan that is located in front of the radiator of the engine, it faces forward and you can see it from underneith the van, it also looks as if there is a smaller radiator that this fan is mounted on and according to hutch, this system is responsable to cool down the tranny fluid.. well, that fan is not coming on, at least it didn't the whole time i was doing all this and the a/t temp red light was still on although i was parked with the engine idling.. so heres my question.. could it be just an electrical deffect with the light board system kind of like how the emergency brake light comes on altough its not on at all? or is that fan supposed to be running and for some reasons unknown, it crapped out and now i'm overheating the tranny? how do i find out and how much is an automatic transmission shop gonna charge me just to tell me, and thats if they even seen that kind of system before! (maybe all automatic tranny cars have that system i don't know)
anybody with a good idea of what i should do drop me a line please!!

[docsavage]

Surferboy,

If you were out playing in the snow, you may have got some crammed up in the transmission cooler. It is a small radiator looking thing in front of the front wheels. There is one on each side - I think one is the transmission , and the other is oil. Also, see if any snow jammed up the front skid plate onto the radiator - it looks like a bit of a snow scoop to me.

The fan likely won't run until the vehicle is up to operating temperature, which in this weather could be a long time.

From other forums and technical manuals, the transmission is a Chrysler unit - same as used on some J**p's so they should be familiar to a mechanic.

Also, the when my alternator started to crap out, the parking brake light and tranny light came on. There is some info regarding this being common on one of the other boards. So check all the electrical connections and tension on the alternator belts as they may be slipping after playing in the snow as well. (I found my snow plow lights in the bull bar drew to much as wired and killed my alternator the first time - the second time was purely my own stupidity)

James

[Mystery Machine]

There are three likely causes of the A/T light coming on:

1) The A/T fluid may need changing. Some L300 owners in Japan spend a fortune making them look nice, but completely neglect the general upkeep of servicing etc...A/T fluid should be changed every few years and not changing it could cause the light to come on ( as a warning!)

2) An electrical problem in the wiring for the A/T system. A sensor lead may have come off the gearbox or engine for example. A wire might have sheared or the contact corroded.

3) The A/T sensor iteslf could be faulty. This is quite possible. I know of 3 or 4 of these going every year in the UK.

I was looking at an L300 only yesterday with gearbox problems. The sensor was the first thing I checked and established it was working OK. In this particular case, the actual gearbox was shot and I've had to find a new one - but the symptoms were totally different to yours and I would check 1,2 & 3 before worrying too much about cooking the tranny.

Just for reference, there are 5 different rads found on an L300 auto.

The main one just in front of the engine is for the engine cooling.
The silver one in front of that is the A/C condenser.
The long thin one mounted in the front grill is the oil cooler.
The one in front of the drivers side front wheel is the A/T cooler.
The one in front of the passenger side front wheel is the secondary A/C condenser.

HTH??

Regards,

Bruce.

[jrman]

Reviving this post based on recent experience.
A/T Temp sensor light started coming on intermittently at first, usually a few minutes after driving - up to 20 minutes later, occasionally not at all. I was not terribly concerned as I checked this post first, and also checked the fluid to find it was the usual nice pink colour, correct level (check on level ground with engine idling preferably after a short drive) and did not smell burnt. The tranny had been serviced a year ago but the screen was not replaced.

Regardless, I had CVI do a tranny service with fluid / screen / gasket (fit me in day after my call and did the work while I waited...tks Edwin!

Sensor light did come back on during my drive home sadly and has since gotten worse until now it is on even at startup (clearly not a temperature issue since it's quite cold outside!!!!!).

Edwin felt the sensor may require replacement.

I checked the tranny again and the fluid is still nice, clean, not burned.

Will check wiring & connections when the weather is better, then try sensor replacement as next step & report back.

Ref: A/T Temp Sensor Dash Light, Transmission Over Heat, Temperature

[jessef]

AT temp sensor.

Mine Pajero did the same thing. Flicker on and off until it was almost always on.

Fluid/level was on the spot and it was an overhauled tranny.

It turned out to be the sensor. Just put a new one in and that was the end of the flickering AT light.

[bosc]

Same problem happening with me. Did about 20km of sand when it first came on, which made sense, but then it never went away (1 month ago). Checked all the fluids- no issue there. my fan does come on however.
Thanks for all the input everyone

[Profister]

My A/T temp light came on twice while climbing to Hemlock Ski Resort recently so I had to stop for cooling down.
BTW where is the temperature sensor located?

[Profister]

Never mind, just found it on UK forum.

[Erebus]

By the way, for everyone's benefit ... but mostly for those who might have real overheating issues, rather than sensor issues.

Directly from the manual, what to do if the A/T warning light comes on:

"If the light comes on when driving, stop the car and place the shift hear in P and idle the engine until the light turns off.
If the warning light does not turn off, contact a Mitsubishi dealer to have the vehicle checked as soon as possible."

Notice that you should NOT just pull over and shut down, but rather idle.

[ExplosiveAbe]

Hey. I had the exact same problem after having service done to my Deli. I phoned Glen from CCAuto to ask if he knew what was up & he said that more often than not, it's condensation in the sensor itself. However, ever since the "cold snap" we've been having, it hasn't come back on again.

[ccautos]

I now have replacement `genuine` temperature sensors in stock if anyone requires a new one.

[madmazda]

an awesome post but has any one seen the size of the exaust on that thing....wow....

[EnviroImports.com]

another delica owner just went through this, and the cause was his alternator. The batteries died, bought one to get home, returned that to crappy---- , put a pair of optimas in, rebuilt the alternator, and now all is good.
Im not sure why his at temp light came on from the alt dyeing, but thats how it went.

[ccautos]

If the alternator is going you would also see the battery light and fuel in water light . There are a lot of these sensors failing right now and it is a very quick and easy fix to replace the sensor with either a used or new one. Would hate to see Deli-owners running out and buying new alternators because their A/T overheat light is on !!!

[EnviroImports.com]

yes i agree, more lights should have been on, but only the at temp light was on. after alot of diagnosis, and the batteries continualy draining , we bench tested the alternator, sure enough it was shot.