ES350 T-mobile Syncup compatability
 

My 2013 Lexus ES 350 is having problems with warning lights staying on: "slip indicator", ABS, etc. The Lexus dealer service told me that the T-Mobile Syncup device I have plugged into the OBD port was causing the problems with communication to the vehicle computer and I should not use it! I contacted T-Mobile and they say it is compatible and is not causing my problems.

Anyone else have any experience with this?

One way to find out. I'd disconnect the device and see if the issue goes away. There must be other devices available to communicate vehicle performance and stats.

Not sure about the compatibility but if you remove the device from the OBD port and the warning lighst go away then it must have something to do with it.

Even if the T Mobile device is the cause of the warning lights, removing the device from the OBD port may not result in those warning lights turning off immediately. The warning lights will turn off only after the trouble codes that caused the warning lights to turn on are cleared from the car's computer.

Eventually, those codes will clear themselves, but, instead of waiting to see if that happens, you can clear the codes yourself with an OBDII scanner. You can borrow one from any of the major chain auto parts stores. They likely will let you take it out to the parking lot, and, once you have hooked it up to the port, it should only take seconds to clear the codes. After the codes are cleared, if the warning lights come back on without the T Mobile device connected, you will know that it wasn't the T Mobile device that caused the problem. If the warning lights don't come back on without the T Mobile device connected, you can confidently conclude that it was the T Mobile device that caused the problem.

As an alternative to clearing the codes with an OBDII scanner, you could disconnect the car's battery for 20-30 minutes and, then, reconnect it, but doing that will cause you to have re-set many of the settings for various systems on the car.

Also, if it turns out that the T Mobile device was not what triggered the warning lights, using an OBDII scanner can help you to track down what the real cause was. Before clearing the codes with the OBDII scanner, you should write down what the numbers of the codes that were generated, and doing a Google search for those codes should tell you what caused them to be generated.

Thanks everyone,
I have confirmed that the T-Mobile Syncup device is causing the problem. T-Mobile says I can return the device for a refund.

That was an easy one. Glad it worked out for you.