Question

My 2003 Mercury Grand Marquis won't start, and I have the p1237 code, I just replaced the fuel pump 10,000 miles ago, so maybe a defective pump?

Answer 1

You probably need to replaced the Fuel Pump Driver Module (FPDM).

P1237 MERCURY - Fuel Pump Secondary Circuit Fault

Read more: https://www.autocodes.com/p1237_mercury.html