Tire pressure light keeps coming on

First, check the tire pressure of the spare. If all tires are properly inflated, then one of the sensors are bad and must be replaced.

That usually means that one or more of your tires has dropped below the level of air pressure that the manufacturer recommends. It is basically a low pressure warning light. This way you will know to find a place to check your tire pressures. Look on your tires sidewall and you will find a cold psi rating and a hot or warm psi rating. The tire pressures need to stay within those parameters in order for the light to not come on. As the tire warms from motion the air inside begins to expand and will read a higher pressure than if the tire is cold. Check your pressures and if any of the tires have a low pressure (below 30 psi) it should be inspected...........Or you may be leaving your emergency brake on. Pull up then push down to release a hand break lever and push all the way down and pull hard on the release lever for a foot brake. Another possibility is the car needs brake pads soon.

The light that you speak of is the Low Tire Pressure warning light. This light comes on if your tire pressures are not at the right pressure. Inflate the tires, and the light should go out.

That light means that you are setting the tire pressure guage. there is nothing wrong with the van.

That symbol is the low tire pressure light. You have a tire that is right at the minimum threshold. The light goes off as the tire temperature rises, and, as the temp rises, the internal air pressure also rises slightly. Just check the tires with a good pressure gauge, inflate them to the specs printed on the tag inside your driver's side door, and you will be just fine.

Thanks for choosing FixYa for assistance.
A FixYa rating (4 blue diamonds) would be greatly appreciated. Thanks in advance.

I also own a 2004 Sienna (AWD, LE)

Check engine lights come on for many reasons, but the tire pressure would not be related unless your computer is malfunctioning which is doubtful. The CEL is for engine related problems, not tires.

There is a tool called an OBDII. OBD stands for On Board Diagnostics. The II stands for 2. This is a standard for all vehicles newer than 1996 and the code it presents you with has a corresponding explanation to help mechanics repair the problem.

I had a code P0420, which translates to a catalytic converter problem, but in fact it was a malfunctioning Oxygen Sensor indicating the catalytic converter wasn't working properly.

Some places will scan your vehicle for free to give you the code, others charge. I bought the tool as it also allows you to reset the light (turn it off) after the problem is fixed or turn it off and see if it comes back on again (sometimes a simple thing like a loose gas cap will cause the CEL to come on).

All tire pressures have to be close to the same to turn of low tire waning. Th change oil is reset easily, and the directions should be in your owners manual.

I have Toyota with TPMS so I have some experience... things that come to mind off-hand are:
- Low tire pressure
- Pressure sensor damaged during replacement of tires

Check the pressure on the tires.... if the pressure is good,then likely one or more of the pressure sensors were damaged by the shop who installed the tires, have them diagnose and replace it/them (at their expense!). Good luck.

make sure all your tire pressures are above 35psi. the light will come on if your tires are below 28 psi. check all your tires for tire pressure. if pressures are low, add air and drive truck at 35+mph for about 1 mile and the light will go out unless you have a sensor problem, but fotha the light will be flashing. so to sum it up, check your tirpressures and make sure, that you have 35 psi in all 4 tires.