I've had four 3rd gens before my current one (TJ advance) and the trip computers have generally been spot on with fuel used and L/100km figures.
But my current one is not reading the fuel usage correctly. It shows about 20% less then actual fuel used e.g. 25L used and it shows 20L used so it shows around 9 L /100KM when it actually did 12L / 100KM.

Anyone had this problem before? I've only just got it so i might try an ecu reset. Anyone know where the trip computer gets its fuel reading from?

Trip computer may not have been set up properly since the last time the battery was disconnected. May be set for a 3.0L engine instead of the 3.5L engine (you get the option first time you turn on the car after reconnecting the battery).

There was a way to check to see what your trip computers set at
I remember Doddski posted it up, think it was hold the 2 arrow buttons then turn the car to ON or ACC

Trip computer may not have been set up properly since the last time the battery was disconnected. May be set for a 3.0L engine instead of the 3.5L engine (you get the option first time you turn on the car after reconnecting the battery).

Yea i didn't even think of that. Will reset it this wkend and see if that does the trick....

As MichellO said. When you firt start your car after having the battery disconected it will ask you on your trip conputer display to put the settings in for it to calibrate itself however I highly doubt that the difference between a 3.0 and a 3.5 would be so much. If the above doesn't work you make want to get an auto electrician to check it out for you.

My TL AWD has never had battery replaced or disconnected at any time. Fuel display is not accurate. I only work on fuel used/km travelled now.

Cheers,
Alan

I've had four 3rd gens before my current one (TJ advance) and the trip computers have generally been spot on with fuel used and L/100km figures.
But my current one is not reading the fuel usage correctly. It shows about 20% less then actual fuel used e.g. 25L used and it shows 20L used so it shows around 9 L /100KM when it actually did 12L / 100KM.

Anyone had this problem before? I've only just got it so i might try an ecu reset. Anyone know where the trip computer gets its fuel reading from?

When the battery was disconnected on my Dads TJ, he didn't set his trip up at all (electronics illiterate).
Was reading figures very similar to what you have said.
Settings defaulted to 3.0 ltr wgn. He has 3.5ltr sdn.
I reset the trip for him with the proper settings and all is now good.

I had exactly the same thing after changing battery, yes it was set incorrectly to 3.0 litre instead of 3.5, & it was showing average about 9 litres per 100ks. went back to normal after i reset it.

My TL AWD has never had battery replaced or disconnected at any time. Fuel display is not accurate. I only work on fuel used/km travelled now.

Cheers,
Alan

Can you be 100% sure of that though? I'd be checking it.

Can you be 100% sure of that though? I'd be checking it.

My TJ AWD only has one option... So you can't really set it wrong.. I'd be surprised if the TL were any different (esp as the TL only got 3.5)

I don't see why you wouldn't check though, they may still have the wagon option in their trip comps.

OK so i have to reset the thing. Does anyone know a way to do this apart from disconnecting the battery and apart from pulling apart the dash?
I don't have the security code for the cd/radio see... and if i disconnect battery it's gonna ask for it. I spose i gotta go to a mitsi dealer for that?

OK so i have to reset the thing. Does anyone know a way to do this apart from disconnecting the battery and apart from pulling apart the dash?
I don't have the security code for the cd/radio see... and if i disconnect battery it's gonna ask for it. I spose i gotta go to a mitsi dealer for that?

its one of two ways (cant remember which right now) - neither of which require the battery to be disconnected and reconnected again

1) hold the SET button while turning the key from OFF to ACC.
that will get you into the check TC settings screem - change and set as requied (tap Set to change, hold it to Store it)

2) hold the SET button, while turning the key from ACC to IGN
then as above to set it up correctly.

for the record - of late, my KL AWD TC average / 100km, used to be reasonably accurate, but right now its telling me its running SUPER efficient and using no fuel.. till the fuel bowser tells me otherwise (and the wallet too...)

When you say SET button do you mean MODE? the main button above the two left/right buttons to the left of the steering wheel?

because i held that down when going from off to acc and it displayed "S" then "3.0" which i know means it's set to sedan and 3.0L engine which is wrong. So i need to change it. But it did not let me change the settings, only displayed them then went straight to the speed alarm thing

??

When you say SET button do you mean MODE? the main button above the two left/right buttons to the left of the steering wheel?

because i held that down when going from off to acc and it displayed "S" then "3.0" which i know means it's set to sedan and 3.0L engine which is wrong. So i need to change it. But it did not let me change the settings, only displayed them then went straight to the speed alarm thing

??

Mode or set - for some reason i always get it wrong!

when you are in that screen, a quick tap of the Mode button, will change the type (3.0 to 3.5) - a hold will set it
(that must be where i continually pull the set button from - setting the mode)

thanks for ur help... i must be doing something wrong (entirely possibly) because when i do that it only displays the body/engine type settings briefly and it does not let me change them no matter how many times i tap or hold the mode button. It only lets me change the speed alarm. i've tried holding down mode and moving the key to different spots to no avail.

thanks for ur help... i must be doing something wrong (entirely possibly) because when i do that it only displays the body/engine type settings briefly and it does not let me change them no matter how many times i tap or hold the mode button. It only lets me change the speed alarm. i've tried holding down mode and moving the key to different spots to no avail.

have you got the owners manual for your car?
or have acess to one at least (mates/family with same model car)?

the proceedure for (it may be slightly different between models) checking and resetting should be in there.
not 100% sure what section its under though sorry

Yep got a manual, this is all it says about it:

"The computer system is coded to the vehicle, which must be recoded if the power is removed from the unit, ie battery is disconnected, or the unit is removed from the vehicle"

Then it goes through the procedure which i already know

and it also says "The "set" code can be checked by holding the MODE button and turning the key from LOCK to ACC"

d'oh.. gonna have to see a dealer for the radio code, oh well