The ABS module doesn't have blink codes

If the light comes on when you turn the key on, goes out once the engine is running, then comes on after you drive for a bit it's likely a bad sensor or bad tone ring on the front wheels.

A simple test you could do would be to lift the front of the car, and using a volt meter on AC, spin the wheel by hand and measure the voltage created. If one wheel is lower than the other you know where to look.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

Where would I measure the voltage?

Current plan is to eliminate control module and relays as variables...then investigate sensors.

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 159k miles
06 E320 CDI "Rutherford", Black on Tan, 178k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 145k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 75k mi
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