Warning lights

Why would you want do do that? Just reset the warning light.

 

Most of the lights are LEDs soldered onto the dash PCB.

If he has replaced the stock wheels or damaged/destroyed the senders the light can be annoying. Perhaps a piece of black electrical tape?

If the light is on and you still have the stock senders on the car, inflate the tires to your desired pressure. Under the steering wheel there are two buttons, one is tire pressure warning system, the other is SKS on/off. Just press the tire pressure warning system button for a few seconds (I think it responds with either a beep or a flash when it resets). Then the light will stay off until the pressure in one or more tires falls more than about 20%.

 

The 'going flat' warning light may come in handy and helpful on a long trip and your psi is decreasing due to a puncture on one of your tires. Hope this never happens, but to me it is peace of mind. But hey...it is your car so you have all the right in the world to disable that light. Perhaps try to pull a fuse out.

 

My wife got the light while driving home, she ignored it 'til she got home, then complained about it, thinking it was a fuel economy thing-gy. The tire had a non-repairable flat before she drove on it so no problem.

Don't get rid of the feature. Its annoying, but, as I read on one of the forums, he over-inflated his tires, reset the pressure, then lowered them down to normal. After that, a 2~3psi drop would activate the light.

 

I am not recommending that you cripple the TPMS warning light. In fact as of 2008, it is a requirement on all new cars sold in the U.S. That said, on p.13-132 of the Bentley manual, there is a one wire Junction Connector from J20(A) to J21(b). It looks like the sole power source to the entire TPMS, including it's ECU, excluding the sensors of course. P.12-18 shows it located somewhere under the dash near the left hand side of the MFD. The experts here on PC should be able the give you an opinion as the whether disconnecting this connection would turn off the TPMS without other consequences or not, since the ECU will still be connected to the communications bus. :noidea: I leave the rest up to you and the more knowledgeable members. :bolt:

 

F.Y.I. It looks like it's powered by the 7.5A ECU-IG fuse in yhe driver compartment fuse box. But it also powers lots of other devices. The Junction connector that I mentioned in the previous post looks to be the only connector between the fuse and TPMS, except the pin connectors on the fuse box and on the TPMS unit. That's why I mentioned it. The switch sounds like it would work. You could probably find a matching hardware to pop out the junction connector and plug in a connector with the wires to the switch. Stealth reversable.

 

I don't have my flatbed scanner set up at the moment. But I'll try to describe it. O.K. Here goes. Using your X-ray vision and looking at the dash slightly above the key slot, there is a cable coming from the front/firewall. It looks like the largest cable in the area between the steering wheel and the console and above the key slot. It looks to be the only major cable in the area. It Y's at it high point. One side goes toward the steering wheel and down toward the accelerator. The other goes toward the console and looks like it runs down the inside of the driver side of the console. Neither seem to have any cables coming off of the main cable. All this was just to find and make sure we have a common reference point. Now back to the point were the cable comes from the front, following it back toward the firewall, it looks like it may Y off to the right and left instead of going into the firewall. Again, just that was just to further verify that we have the correct cable. Between the two Y's mentioned and toward the front Y or possible at the Y, maybe it's actually a W. There's a small cable or 2 cables running parallel, that runs forward and stops just above the Power button. Oh! almost forgot, according to the wiring diagram, they should both be solid black wires.
It looks like the Junction Connector for J20(A) & J(21(b) are at the end of this short cable. Good luck! Watch you knuckles. Let me know how you make out.

 

I'm guessing without power it will be disabled. My concern is that the TPMS will still be connected to the communications bus(es) and I have no idea what, if any problems that could possible cause. You may want to see if you can PM some of the technical experts over in the Technical discussions forum. "Danny" the administrator may be able to help you or point you to someone who can. While I would think that it would be designed so that lose of power, blown fuse, wouldn't hurt anthing; you may want to play it safe. That said, I would make sure everything else seems to be working, no problems with the TPMS connected to the communtcations bus w/o power to it. If all seems O.K. then the warning light will either come on at some point or not. At the risk of getting beat up by other modification prone members, I feel the obligation to run this thought by you, as remote as the possibility may be. Since it is now a federal requirment on all new cars beginning 2008. And since your's is a 2008. If, God forbid, there would be an accident that insurance company lawyers could construe could have been avoided, had the TPMS not have been disconnected, well????? :noidea: I know there are members that didn't like to be reminded of these issues. And it is strickly a personal choice as to whether it is a risk at all and a personal decision whether to risk it or not, if concidered to be a risk. I don't mean to be a spoil sport. I just, personally, like to know as many of the pros and cons as resonably possible, before I make a decision that could affect the safety or wellbeing of me, my family or others on the road. That said, good luck on whatever your decision.