Voltage spike when braking

TAA1971

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Joined
Aug 23, 2024
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3
Location
Wisconsin
2012 Rubicon. Getting C2101, C2103 & C102B when braking hard. The battery, ABS & traction control light come on, but can be reset when turning off/on. Changed the wheel speed sensor and connector (I broke the connector). I can see the voltage spike to around 16 volts on a graphing scanner when I brake hard, but goes back to normal immediately (just a spike). Someone has added a lot of extra lights. I disconnected those, to no avail. The TIPM and alternator have been replaced. I added ground wires, frame, engine, body. Also, get the same issue when I pulled all the fuses related to the ABS and shut off the ABS temporarily with a JScan. The wheel bearing feels good. I've read all the other threads and am completely stumped. TIA!
 
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not specifically, but it doesn't happen in reverse or just parked. I would think if it was a brake switch, it wouldn't matter if I was moving or not. Correct?

It makes sense to me. To rule out, have you braked hard in park and reverse though?
 
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