What does the c diff auto light on dashboard means?

Toyota Dashboard Lights Symbols Guide

If you have the Check Engine and trac off light showing at the same time you have a serious issue. Take the car to Toyota in that case.

CHECK OR HAVE SOMEONE CHECK BRAKE FLUID LEVEL, BE SURE PARKING BRAKE IS NOT ON!

How to read Toyota warning lights. - YouTube

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Oct 21, 2012 - Uploaded by NinjightNationCorp This particular Toyota is a Camry. Check out my ... Years 2000 to 2010. ... Car Problems - What Do the Different Dashboard Lights Mean?

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That means that the center differential is locked, making it 4-wheel drive, but restricting the tightness of turns that it can take. You should not operate it on dry pavement or above 45mpg in C DIFF LOCK mode or it could damage the car.
To turn it off, drive it to a level spot, stop, and press the button to turn it off. Drive a few feet forward and wait for the tone to go off. If necessary, put it in revers, drive backward a few feet and then go forward. That should turn the tone off and the light.

Driving a vehicle with diff lock on hard surfaces will damage the drivetrain. Try to avoid this. If your center diff is locked, be sure to press the button on the dashboard (Center diff) to the off(button out) position. (Yes, you didnt press the button, but your model automatically engages diff lock in 4lo) So dont engage 4lo on hard surfaces.
Try reversing a couple feet. This may free up the diff so that the lock can disengage. If this does not work, find a large patch of grass or gravel. Turn the steering to full lock(left or right, doesnt matter) and pull off. This should disengage the lock. It is good practice to engage the difflock at least once a month as this will keep the lockers lubricated enough so that they dont bind like yours have done.

It mean that even with lights off, when it becomes dark enough, lights go on themself (exemple: when drive in tunel...) cover sensor on windsheld with your hend and lights should go on.
Marko

that figure looks like your abs auto brake system. Check your break system.

this is a traction control fault indicator light. this is most commonly caused by a faulty wheel speed sensor. you'll want to bring the car into the shop to be hooked up to a computer for a proper diagnosis.

Two things happen when you select 4WD in this car. Moving the transfer lever physically selects the gears that will turn the prop shaft to the front diff. At the same time, a switch in the transfer box tells a pump to supply pressure to the diff engagement diaphragm in the front diff housing. This joins the diff spider gears to the front drive shafts. Once the air pressure remains fixed, the 4WD light on the dash will remain lit solid. Obviously, a number of problems could be causing your lack of 4WD. The most common would be the air line(s) from the pump (behind the front bumper, LH side usually) to the diff being pulled off, cut, or crushed during 4WD'ing. Failure of the pump, the relay control unit that powers the pump, the switch that turns it on and off are all possibilities too. As you have no 4WD lamp on the dash, you may have a blown globe too (unlikely) as this should flash if air pressure can't be maintained. You would still have 4WD! See if you can select 4WD with the ignition OFF and listen for any relay or pump noise. I'm not sure you can actually do this without the engine running, but it will be a lot easier to hear with the engine off. If you can hear the pump and everything else is OK, The problem may actually be in the diff. Good luck.