I have an 03 Mercury Grand Marquis 4.6l V8. The car will not start, crank or anything. when you put the key in all lights on dash board and headlights come on. when key is turned there is no dimming on the dash or in the headlights. I have replaced the battery, starter, solenoid, ignition switch, and ignition coil. previously before the car stopped working I just replaced a cracked intake manifold 2 weeks before the car stopped working. I was in the middle of installing a sub system in the car when it decided it wasn't going to start anymore. I pulled all of the audio cables out and checked all my connections, still nothing. Someone said something about the black box might be bad. I didn't know cars had a black box, but I'm not convinced that's what it is. I have been without this car for 4 months now and no one knows what to do. Any suggestions?
I found this service bulletin I hope this helps you.
You can also check the voltage at the starter terminals when you try to start the engine and trace the wires back to the starter relay to see if it the problem is before or after the starter relay.
Let us know if this information helps you with your problem.
NO CRANK / STARTER TERMINAL FATIGUE
1997-2007 Crown Victoria
1997-2004 F-150 Heritage
1999-2006 F-Super Duty
2007 Explorer Sport Trac
1997-2007 Grand Marquis
Some vehicles may exhibit a no crank condition due to an open circuit in the starter relay to starter motor circuit at the starter motor connection.
Follow the Service Procedure steps to correct the condition.
A new starter terminal wiring pigtail kit is released eliminating the need to replace the entire harness for the terminal connection.
NOTE TERMINAL KIT ONLY SERVICES THE STARTER RELAY TO STARTER MOTOR CIRCUIT. THE KIT DOES NOT SERVICE STARTER MOTOR BATTERY POWER CIRCUIT.
Refer to instruction sheet contained in Wiring Pigtail Kit for wiring harness service procedure.
6U2Z-14S411-NA Part number for wiring pigtail kit. You can get this at your local Mercury dealer.
i have tried that before as well. everything looks to be good.
*while we were putting the audio wires through the firewall we followed a wire running right through the firewall that leads directly into the steering column, but it was blocked. so we cut the rubber around the line to unblock it. could this have damaged anything? the line seemed to be a thin steel like line that i didnt see any cuts into. but not sure if we may have damaged the line. any thoughts?
If that wire you are talking about comes from the ignition switch it could be part of the problem. Find the end of the wire and back probe the wire to see if you have current to it when the ignition switch is in the start position. See if this wire is the one that powers the starter relay. If you don't have power to the relay the engine won't start.
I listed the starting system description below. I hope it helps.
The starting system consists of the: starter motor, ignition switch, digital transmission range (TR) sensor, mini ISO relay, Starter Motor.
The starter motor: is a permanent-magnet, gear reduction, 12V DC motor. It
has an integral starter solenoid.
The starter relay: is a mini ISO relay. It switches power to the starter solenoid to engage the starter motor when it receives a START signal from the ignition switch.
When the digital TR (transmission range sensor) the sensor recognizes that the vehicle is in either PARK or NEUTRAL and the ignition switch is placed in the START position, it sends a signal to the mini ISO relay that, in turn, sends a voltage signal to the starter solenoid, which will engage the starter motor to crank the engine at a speed fast enough to permit the engine to start.
This information is from the Alldata automotive information website.