the van has been going fine since I had the lamba sensors done ,
had a minor problem with the battery going flat when the van wasnt used for a few days but traced that to the relay for the auxillary towing socket that charges the battery on my caravan , water had got into it and caused a short so the socket was permanently live instead of only on with the ignition.

however a few times recently the engine check light has come on whilst driving ,

usually accompanied by a jolt underneath the car ( probably the gearbox going into get you home mode i.e. locking in third gear ).

there is no prior warning when this happens and no obvious reason for it , it can happen at any speed , going on the flat , uphill or downhill .

If I pull over and turn the ignition off for a minute or so it clears and the car is back to normal .

it is completely random sometimes happening again in a few minutes sometimes not for a week or two

anyone have any ideas please ?

I suggest you have the auto box fault code read as it will put the engine management light on when it goes wrong

Hi

This is exactly the same problem that I have. At least now I know that there is "take you home mode" and nothing is wrong with the gearbox. Could you please give us an update what happened next, did you read fault codes?

to be honest not yet ,
the fault happens so randomly
( I presume the fault code will only show when the engine check light is on )

it was fine thursday friday and saturday last week.
happenned once on Sunday and hasnt happenned again since .

the only problem is the lack of get up and go ( ie pulling off lights etc until you find a safe place to pull over and switch off.)
and the lack of power in reverse

However I have found out you can overcome this by manually changing down to second

I believe you presume wrong...the "box" will also store fault codes..you can get a kid at Autozone to read it for you for free if you dont want to go thru the hassle of the service dept....or...you can buy a code reader...handy lil thang...but since its intermittent, you could also wait till it wont go off, usually in the middle of the night 200 miles from home...early Sun AM....in the rain.........with folks in the car....etc etc...

Hi mickey taker


Read the error code , it is stored there.
My guss you have a fault in input or output
speed sensor . code PO 725 , or po 720 .

if this is the case changing any of these sensors is dead easy .

if any of the 5 Auto tranny solenoide , it is it a bit defficult to replace .



Regards

Thanks for the update. marrug is right about codes. I was at a local garage (not Hyundai certified) and they red codes PO715 and PO711. Google says:
PO715-Input/Turbine Speed Sensor Circuit Malfunction
PO711-Transmission Fluid Temperature Sensor Circuit Range/Performance

I know that these fault codes are newly created because the same garage tried to read them some ten days ago and the results were a bit confusing so they deleted all codes and we were waiting for it to happen again. My dilemma now is how serious and complex this is. Can I continue with a local garage or do I have to contact Hyundai certified one? Unfortunately I can't find any technical documentation for Trajet.

This post has been edited by dadel: Oct 15 2008, 05:40 AM

I hate to use dealers to fix things unless its under warranty..having said that, theres a few types of problems that they can diagnose/fix way better than the average shop...mainly because they see them ALL THE TIME...this is one of those things..good luck...

Thanks for your opinions. I don't like dealers either, especially in this case. Hyundai is popular in Poland but they don't sell Trajet here. I've imported it from Sweden (crazy idea) and Hyundai garage charge me fortune for every single thing :(

I think I drive to auto electrician to check if these two sensors are really broken:
- input speed (PO715)
- transmission fluid temperature (PO711)

I would really appreciate any help in locating these two. I found mazen's post on input/output speed sensors but I have problem understanding it. mazen, can you describe it in other words so that even I can understand :) Can anyone describe the location of the "transmission fluid temperature sensor" and what are real/nominal values for these two sensors?

Thanks

This post has been edited by dadel: Oct 16 2008, 02:04 AM

Hi

Can anyone help me find the input speed sensor, is it the one on the top and in the mid of the transmission just under the air filter box connected with, I think 8 wires, or is it the smaller one on the left side connected with only 3 wires?

ok , finally got around to having the error codes read

came back with PO 715 which as we have said is -Input/Turbine Speed Sensor Circuit Malfunction

but I am also getting USBOO which is a Hyundai manufacturers code and my garage cant tell me what that is for

does anyone know how hard to fit and how expensive is the faulty sensor to replace and does anyone know what the other code means ?

Input speed sensor in the gearbox or the gearbox itself. Check the gearbox oil level first after a twenty mile run. Top up if nessercary. Forget the USB code. I can only tell you the part number if you pm me your chassis no.

This post has been edited by Hyundaiownersclub: Nov 20 2008, 03:06 PM

took the car to my local hyundai dealer yesterday afternoon they sorted out my airbag light ( there was a high resistance in the passenger side circuit causing it to come on ) and read then reset my codes ,
they said the error code was a historic one and hopefully they had sorted it out ,
four hours later the light was back on.

I found these two guides to sensor replacement for the v6 sonata and wondered if it was the same process for the trajet


first one

At home I don't have access to part numbers. The sensor itself is kind of a pain to replace. It is under the shift cable and has a 3 pin wire connector that can easily be broken if man handled. To replace remove the 2 12 mm bolts that hold the shift cable to the trans case and push the cable away from the sensor. DON"T try to un plug the sensor yet!!!! Remove the 10mm bolt that attaches the sensor to the trans case. Twist and pull the old sensor from the case. Now push the release tab on the connector and disconnect the old sensor. If the sensor won't un plug a hair dryer will warm up the plastic and help release the connector. Installation is the reverse of the romoval. You may also want to disconnect the negative battery cable during this repair. This will prevent the posibilitys of shorting out wires, clear any trouble codes and allow your trans computer to "Re learn" how to shift with a new and operating sensor.
Mac


and secondly more step by step

The input speed sensor is located on top of the transmission,
underneath the bracket attaching the shift cable to the transmission.
To replace:

1. Loosen the air intake hose clamp at the throttle body (may require
removing engine cover).
2. Unplug the air flow sensor connector.
3. Remove the three 10mm bolts holding the air box in place. One
will be under the fuse box. If you don’t have a long extension and
10mm swivel socket, you’ll need to remove the battery.
4. Remove the air box.
5. Remove the two 12mm bolts holding the shift cable bracket.
6. Clean the area around the speed sensor.
7. Remove the 10mm bolt and remove the sensor from the hole.
8. Unplug the sensor from the wiring harness.
9. Make sure the hole is clear and install the new speed sensor and
the 10mm bolt.
10. Attach the electrical connector.
11. Reattach the shift cable bracket.
12. Reinstall the air box.
13. Plug in the air flow sensor.
hopefully its a similar / same process for the trajet

Hi All

I do not understand why the gussing is for . all the required information is
available in the workshope manual and ready for downloading . check the
opening page of the forum it is pined there .

changing the input, output sensors is very easy, A/T fluid temp. is a bit diffecult , because you
have to open the fluid case to get there , resistance for sensor at 25c is at the manual .



regards