bloodvette

05 4x4 Lariat Screw 5.4L. Getting the ABS light on immediately at start up. this usually means a bad wheel speed sensor and that it's not reading the proper resistance on one of the wheel speed sensors... Does anyone know what the correct resistance of a wheel speed sensor should be? this will help me pinpoint the faulty sensor if there is one.

I know I had a similar problem with my corvette and a good working sensor shows 11 kilo-ohms for that vehicle.

of course I'll figure it out when 3 of my 4 are the same but just incase someone knows this info off hand. thanks.

john

bloodvette

is there only one wheel speed sensor for the rear wheels which is located on the rear differential?

GATORB8

Service manual just says current in the wheel sensor circuit should be btwn 6.3-15.4mA, so that should be somewhere between 780-1900 ohms at 12V.

GATORB8

Correct

bloodvette

I measure 650 ohms on each of the front sensors and my rear one appears to be open circuit. I also tried starting the vehicle with a front sensor disconnected (to simulate an open circuit sensor) and in addition to the ABS light being on, also the Brake dummy light is also on. I confirmed that with either front wheel sensor disconnected it illuminates this light and goes out once the sensors are reconnected and engine restarted. I do find it unusual that my rearend speed sensor is infinite ohms- ie. open circuit. Wonder if this is my problem. Tomorrow I'll try disconnect IT and see if there's a difference in the dummy lights.