Will not start after replacing the battery with a weaker battery

Hi,

This is straightforward as to what needs to be checked. First, here is how it works:

Power is supplied via the ECM B fuse under the hood to the fuel pump relay. At that point, the relay is open and the power stops.

For the relay to actuate, it has to receive power from the PCM fuel pump relay circuit. When that power is applied via a dark green wire with a white tracer, the relay actuates and allows power from the ECM B fuse to travel to the fuel pump.

So, start by checking and testing the ECM B fuse in the under-hood fuse box. If it is good, confirm there is power to and from it.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-a-car-fuse

IF that checks good, go to the starter relay in the same box. Remove the relay and check to confirm there is power to pin 3. If there is power, you need to confirm a voltage signal to the dark green/white wire at the relay (pin 2) when the key is in the start position. (See pic 1 below)

IF both have power, inspect the G119 and G416 ground for continuity to ground. See pic for ground locations.

Here is a link you may find helpful:

https://www.2carpros.com/articles/how-to-check-wiring

Do this and let me know what you find.

Take care,

Joe

See pics below.