sprocket

A couple of days ago the TPMS light started flashing on my 2004 GX. This morning I took it to a trusted tire shop. They checked each sensor, including the spare, and found they were all sending a signal. At 11 years old, and they are original as far as I know (I've owned it about 7 years), the tech said the signal may be too weak for the ECU to pick up. He didn't want to start changing sensors in the event it is an ECU issue. Not sure what to do for now, other than leave it alone.

Any suggestions? Is there a way to confirm the ECU is good? Do the scanners tell how strong the signal is?

BlackCat81

The truck should have a code stored if you have a flashing light. It'd be in the chassis section. Something like C1711 no data or similar. A TPMS relearn tool won't tell you the code.

sprocket

Would a reader at a place like Autozone be able to tell if the ECU is good or not?

Lumbergh

The TPMS sensor on my 2008 GX came on the other day as well.

Checked the tire pressure on all 4 tires, then the spare. The spare was low.

Refilled spare and light did not go out. Found and pressed the button under steering wheel and light went out and has not returned.

Might try that.

Good luck.

BlackCat81

No, they typically only read power train codes.

sprocket

Is the logical next step a trip to a trusted facility to whether the ECU is bad? Is it possible one of the sensor batteries is simply low and the ECU isn't picking up the signal but it is strong enough for a scanner to recognize?

If I wasn't close to trading it in/selling I'd live with it.

roemer7

I agree with Lumbergh. Push the tire button under the steering wheel. That should fix the flashing TPMS light.

sprocket

'll try, but remember, it is flashing, not just on. This represents a system fault, not that pressure is low.

z2g2gs

I recently purchased a 08 GS350 and on the test drive noticed the lite on and message center showing low pressure. We checked the pressures which were low, salesperson ran car through shop, I asked them to put 35 psi in the tires. When he came out light and message were gone, I questioned him if they just reset system and light might come back on. I live about a two hour drive away and lo and behold light did come back on and was flashing. Before I got home it did go off but then came on then again, and flashed several dozen times before going steady. When I arrived home I rechecked air pressures. Hum, 32 to 33 psi. I reset the pressure to 35 which I have since raised to 40. No more light. I did read in tips and tricks about setting a lower set point on the system but haven't tried it yet. I like you figured light flashing and due to age of car there was a weak sensor or something. But adjusting the tire pressure has worked for now. I have put around a thousand or so miles on car since and still no light flashing or otherwise.

roemer7

In my case, the light was flashing because the tire a/b button had been pushed. The GX is set up to accept two sets of wheels. The system was looking for the second set of wheels and flashing the light because they weren't there - system fault. I pushed the button back to the "a" set of wheels and the light went out.

sprocket

Gotcha. It's possible I may have accidently hit the button. My GF drove it a few days ago and when I next got in, the seat was forward. I'll check when I leave work today.

roemer7

My wife is short and I'm sure the same thing happened to me. I hope it works.

sprocket

No luck. I did push it while driving. It was in the "out" position.

mojo08m

I would be willing to bet that you have a dead sensor and here's why:
Each of the 5 tire sensors runs off of a battery that has a life expectancy of 10 years (congrats on getting 11 out of them). The tire shop you took it to may have actually picked up a signal from a different tire twice or from the car next to it giving him the impression that the sensor was functioning properly. The only way to know for sure if you have a dead sensor is to hook up a scan tool to the vehicle and compare the sensor codes in the data list to the sensors that the activation tool are picking up. The probability of you having an issue with the TPMS ecu is HIGHLY unlikely but possible especially in the case of rodent damage. But, like I said earlier, you probably have a dead sensor.

sprocket

Is this a dealer issue or do you think a trip to a different tire shop may be in order?