Tow Haul Light Flashing
 

Tow haul light started flashing a couple weeks ago after pulling trailer home from desert. Next day everything is ok. Now tranny sometimes will not upshift while reving up to 3500 rpm. The check engine light next to the ABS stays lit now. Truck is 2006 FX4 250 6.0 with 10,000 miles. Any ideas?

Ya... take to dealer as you have a tranny problem.

Have you ever changed your fluid and/or filters... and if so, was it doen on time and with the proper fluid? Only Mercon SP must be used and use of non-Mercon SP has been shown to cause problems.

Could be a sensor, low fluid or something else. Tranny is covered under the 3/36,000 warrenty of your truck - if you still have warrenty left?

tow haul light flashing
 

If you also lost the tach, speedo, cruise control and the ABS light stays on, have dealer check the rear ABS sensor. Just had mine replaced in '06 F250 with 11,000 mi. Apparently there is a connection prone to cracks and corrosion.

Get that thing to the dealer before it leaves you stuck somewhere. My truck made it about three miles after that light started flashing until major transmission failure.
Hopefully it is just a plugged inline filter or something simple

I took truck in today, dealer called 5 hours later says all done. They also did the latest reflash on the '06. Service tech says tranns probem might have been cured with this latest flash. Hard for me to believe this fixed trans, as the trans would not upshift and tow haul light was flashing. Check engine light is also out now. What do you think?

Anything is possible.

Hopefully they checked (plus you may double check):

1) Fluid level of tranny?

2) How many miles - is it due for servicing or close too - plugged filter?

3) Save receipt and drive and see what happens... take back and ask for loaner as it is the second time (if indeed the problem comes back).

4) I would ask (for your piece of mind) what did they do besides re-flashing?

Good luck... drive and see.. then let us know.

Anything is possible....

Hopefully they checked (plus you may double check):

1) Fluid level of tranny?

2) How many miles - is it due for servicing or close too - plugged filter?

3) If you have ever serviced the tranny was Mercon SP fluid the only fluid used?

4) Save receipt and drive and see what happens... take back and ask for loaner as it is the second time (if indeed the problem comes back).

5) I would ask (for your piece of mind) what did they do besides re-flashing?

Good luck... drive and see.. then let us know.

Truck only has 11,000 mi., fluild level was the first thing I checked before taking it in, this was the first time truck was in for service. Drove today with no problems, did notice the injector motor noise after shutting down.

It should have thrown a code with ABS or check engine light on and it must not have been one that showed any problem. Its nice to be able to read codes before going in so you know what could be wrong but if its a good service dept I'm sure they will take care of you and I wouldn't worry about it. You have 3yrs 36k warranty and if there is a problem that the flash doesn't fix you got time for it to show its ugly head again. I would try to take a trip like the one when you had the problem at first and see if it happen again . That way you will know for sure .


Good Luck

When the tow/haul light flashes....a code is thrown.

The PCM controls the motor and the TCM module controls the tranny.

On another site I read where others had reported the same problem abd that aftermarket code readers do not read Ford's TCM, but rather just the TCM.

The problem (or code thrown) was a faulty temperature sending unit in the tranny. The fix was to drop the pan, replace sensor and replace and refil.

By re-flashing your computer (probably both PCM and TCM) just reset the code/memory... and probably did nothing for the faulty temperarure sensor. Again... I would ask if they tried to read any or all codes before uploading the latest flash... or did they just uoload the flash and "hoped for the best"???

The other site mentioned that the truck could loose power or go into "limp mode" as the computer tries to make sure the tranny does not overheat or forces one to go to the dealer for inspection.

For now... you may need to drive until it happens again then take in... as they will need to see/read the code before they will fox... or even know what to fix.

Good luck!!!!

i had a similar issue yesterday 2006 f250 with 5.4

drove to the gate at the job site open the gate went to get back in the truck tow haul lite was flashing and abs light was on, fluid good has 97,000 miles on truck drove 1/4 both lights went off and truck drove fine , but its still in the back of my head WHY did it do this.

maybe mine needs a reflash?

No, it doesn't need a flash. It needs someone with the right scan tool to read what code was stored in the computer's memory. Then someone can diagnose what's wrong.

The original poster of this thread more then likely had a TFT sensor go bad, and the Reflash done nothing. Since he only had 11,000 miles on the truck it was fixed under warranty. When a transmission code is thrown the tow/haul light will flash.