While driving Infinity I35-the battery light and brake light came on. Then the car shut off and it would not come back on, replaced the battery but both lights remain on? What can this be?

Question edited for clarity and toss in some CAPS.

There is nothing that backs up memory. When you disconnect the battery, all memory is lost, which is why it is important not to do it!

You don't tell us the model? Is it a secret? All questions need 'year make model' as the FIRST 3 words.

If your have a 1999 Infinity I30, the ECM Fuse is Fuse 58.

58 10 Engine Control Module (ECCS), Mass Air Flow Sensor, Crankshaft Position Sensor, Idle Air Control Valve (IACV-ACC) Solenoid Valve, Ignition Coils, EGR, EGR Volume Control Valve, EVAP Control System Pressure Sensor

Infiniti i30 (A32; 1995-1999) fuses and relays

Fuse Box Diagrams https://fuse-box.info > infiniti > infiniti-i30-a32-1995-...

Fuse box diagrams (location and assignment of electrical fuses and relays) Infiniti i30 (A32; 1995, 1996, 1997, 1998, 1999).

Infiniti i30, i35 (A33; 1998-2004) fuses and relays

Fuse Box Diagrams https://fuse-box.info > infiniti > infiniti-i30-i35-a33-1...

Fuse box diagrams (location and assignment of electrical fuses and relays) Infiniti i30 / i35 (A33; 1998, 1999, 2000, 2001, 2002, 2003, 2004).

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I don't know if this could help you or not but I have a 2004 Infiniti G35 sedan and my brakes lights went out and I couldn't figure it out and I'll be damned if it wasn't in the wiring harness that comes down when the trunk closes there's a little one to the right there and I don't have a 2004 but don't count that one out you have to split it and you'll see that the wires somehow just got dry and cut from the sleeve and I just rewired it boom back together and it runs and it stops with brakes lights anyways good luck.

Sounds like there's a problem in the charging system. It could be as simple as a loose fanbelt, or as major as a bad alternator. I have a very similar car, 2004 Infiniti I35, same engine/alternator, and my alternator went bad in November. Replacement is a pain, the book calls for removal of the AC compressor, though my mechanic pulled the radiator instead.

If you want to solve your problem, click on the link I attached 2004 Infiniti I35 Service Repair Manual INSTANT DOWNLOAD

hi, i have infinity fx 35 2003 it light on the service engine camshaft position sensor bank 1 , i replaced the bank 1 after 3 hour it light on again service engine + VDC off and slip i put the scanner it told me camshaft position sensor bank 1 again what can i do ?

Bad alternator.

Yes you can use Premium Unleaded Gasoline in your 2004 Infinity I35. Infinity actually recommends Premium grade gasoline for your car!

Doesn't sound like the brake lines were bled properly. Many times after pad and rotor installation if the lines are bled correctly you will have to pump them initially after the repair for a couple of minutes until the pressure is built back up. Also check the master cylinder and make sure fluid level is ok.

I had the same problem with my 96 Nissan/ infinity g20.
If I turned on the ac the brake & battery lights came on, the AC fan would work but the air did not blow cold. Disconnected the battery for a few hours to reset the computer. That solved the problem.
Now, no lights, and the AC blows cold.