Repeated Tire pressure warnings?

[Maxhouse97]

Have had several over the last few weeks, everytime the tires are fine. And I have followed the complex TPMS reset process. Could this be bad wheel speed sensors? Car is a 2004 and has 134k miles. I’ve also received ABS lights and traction control lights after a track event that all eventually reset. Thanks.

[Estoril]

I assume that you have checked same-axle pressures and matched them? Also assuming that you are using the "Key position 2" procedure for the relearn new pressures process.

If you have seen traction control lights when traction is not an issue, I would pull, clean and check wheel speed sensors.

[Maxhouse97]

Yes I have, will confirm again though. The connection to the ABS and traction control made me think of the wheel speed sensors as well. Didn’t know you could just clean them. Will check that too. Thanks.

[Estoril]

Yes I have, will confirm again though. The connection to the ABS and traction control made me think of the wheel speed sensors as well. Didn’t know you could just clean them. Will check that too. Thanks.

The WSS can have metallic/iron dust stuck to them like a magnet. If that doesn't clear it, there is a DIY WSS test:

Digital volt meter (DVM). Connect the meter leads to the wheel speed sensor - polarity doesn't matter. Select the milivolt range (mV). Spin the hub and observe the meter. You should read between 1 and 5 mV when you spin the hub. No output = a defective and/or dirty sensor.

[Tbonem3]

Estoril

How are you connecting the multimeter's leads to the sensor? What metal is exposed, with the sensor installed, that you're touching, to get a reading while spinning the hub?

[Shonky]

Estoril

How are you connecting the multimeter's leads to the sensor? What metal is exposed, with the sensor installed, that you're touching, to get a reading while spinning the hub?

Presumably means unplug the connector and measure the circuit. They are powered sensors though so not sure how much you'll get out of them without powering them - that may explain the very small expected 1-5mV cycling. I presume across signal output wire and ground. If you could back probe them connector whilst powered you'd get a better result I expect.

All that said though, an intermittent or noisy sensor like you might get with the metal cruft on them may be hard to distinguish with just a multimeter.

[LeeForst]

I’ve actually had this recently also - red light coming on my pressures are ok. I’m an 2004 and have tracked a few times. Wonder if it’s the PFC 11 dust. Good info on checking WSS

[Tbonem3]

I’ve actually had this recently also - red light coming on my pressures are ok. I’m an 2004 and have tracked a few times. Wonder if it’s the PFC 11 dust. Good info on checking WSS

Same, but textars, which are also pretty dusty, but I doubt it's recent accumulation. I'll try cleaning them. Wish the computer would tell you which of the 4 is throwing the fault