Hi,
The brake switch isn't a likely cause unless you noticed the brake lights aren't working. I believe I understand what you are experiencing. In this case, the first thing I suggest is to check is the start 1 relay. It may be failing.
If you look below, I attached the wiring schematic for the starting system (smart key/push button). I highlighted the relay I'm referring to. It won't be a fuse or anything like that because it would never work if it was blown.
The relay is in the underhood fuse/relay box. If you look at pics 3 and 4 below, it shows the location and I highlighted the relay.
Try this: Switch that relay with a different one in the box having the same part number and see if the problem still occurs. Or, here is a link that shows how to test a relay. My concern is it doesn't happen all the time, so testing it may not provide an accurate result.
https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit
Now, please keep in mind that a weak connection to the battery can do this as well. Make sure the battery terminals are tight and clean. Also, follow the ground wire from the battery to the engine block and confirm it is tight and clean as well.
If this all checks good, you may simply have a faulty solenoid on the starter causing this. The idea that it clicks (bumps) indicates the circuit is complete. So, we are losing power at some point. My guess is either a bad connection, a faulty starter relay, or the solenoid on the starter itself.
I hope this helps. Let me know what you find. Also, pay attention if the brake lights are working properly when this happens. You will likely need a helper. LOL
Take care,
Joe
See pics below.
Images (Click to make bigger)
Sunday, June 13th, 2021 AT 6:32 PM
