Did that fix resolve this problem? Did you encounter the same issue with the R303 relay again?
If you ask me - yes, it help and I use standard 30A relay, not "mini 20A" ( in my opinion 20A is overrated for this relay to work long time )
On my profile I have a question:
"Hello. I was just curious why you think the problem is the fuel pump?"
Because your relay is rated for 20A. Fuel pump need to work about 15A. If your pump's motor starts to seize and has greater resistance, then the pump's power consumption increases. If rise above 20A can destroy your relays. If relays is melted after 20 years it can be because overheating, but after few days ?? For me it means:
- too much current flow through the relay
- factory damaged relay
- damaged/overheated relay solder pads
"Is there a way to check if the fuel pump is causing this issue before replacing the fuel pump?""
You can measure pump power consumption with multimeter device with 20A current probe possibility. You need to connect the meter probes in series with the pump power cable from the relay and start engine. You will see power consumption of your fuel pump. It will be good to drive and observe. Sometimes current rise with temperature and it need time.
If you observe that high current is not your problem, check solder pads on PCB. Look on my photo with pin description and remember:
- PIN 30 ( main power sypply ) is solder to circiut from bottom side
- PIN 85 and 86 ( relay coil supply ) are solder to circuit from bottom side
- PIN 87 ( pump power supply ) is solder to circuit from upper side - it means that you need to use more tin and heating time to make good contact. If you don't do it right, the pump will not start or stop working. Maybe this is your problem.