Ignition fuse pops when braking at low speed or stationary

[DanForceSix]

2006 BF FPV Force 6

 

While driving at around 10kph or less and sitting stationary, my force 6 will consistently pop the 15a Ignition fuse when applying the brakes

 

Started the morning of all ford day in geelong after already driving the car for a couple of hours prior. 

I had a similar problem about 18 months ago that turned out to be a factory sleeved ignition and boost control wires coming out of the ecu that had rubbed through on the top of the strut tower

this was repaired and another ecu was married to the car, for some reason the origional ecu had become faulty and could not be tuned via pcmtec after that wire issue

I doubt that it has anything to do with it but any electrical issue with the car has been AFTER the stage 3 zf trans tailshaft and trutrak/ims hat was installed and tuned ( then driven for a year )

has anybody else had this problem

[k31th]

seems like something an auto-elec should be sorting out... seems a bit complicated, if it happens when you apply the brakes 😮 

[Ralph Wiggum]

Get your engine mounts checked out

[devidevighst]

On 24/04/2025 at 3:33 AM, DanForceSix said:

2006 BF FPV Force 6

 

While driving at around 10kph or less and sitting stationary, my force 6 will consistently pop the 15a Ignition fuse when applying the brakes

 

Started the morning of all ford day in geelong after already driving the car for a couple of hours prior. 

I had a similar problem about 18 months ago that turned out to be a factory sleeved ignition and boost control wires coming out of the ecu that had rubbed through on the top of the strut tower

this was repaired and another ecu was married to the car, for some reason the origional ecu had become faulty and could not be tuned via pcmtec after that wire issue

I doubt that it has anything to do with it but any electrical issue with the car has been AFTER the stage 3 zf trans tailshaft and trutrak/ims hat was installed and tuned ( then driven for a year )

has anybody else had this problem

 

It sounds like a short circuit in a circuit that’s triggered when you press the brakes—most commonly the brake light wiring or a shared ignition feed that’s rubbing through and grounding out under load.

Given your previous issue near the strut tower, I’d start by re-checking the wiring loom around the ECU, the brake light switch, and the rear light circuits, because it really sounds like an insulation or chafing problem has come back somewhere in the harness.

[devidevighst]

On 24/04/2025 at 3:33 AM, DanForceSix said:

2006 BF FPV Force 6

 

While driving at around 10kph or less and sitting stationary, my force 6 will consistently pop the 15a Ignition fuse when applying the brakes

 

Started the morning of all ford day in geelong after already driving the car for a couple of hours prior. 

I had a similar problem about 18 months ago that turned out to be a factory sleeved ignition and boost control wires coming out of the ecu that had rubbed through on the top of the strut tower

this was repaired and another ecu was married to the car, for some reason the origional ecu had become faulty and could not be tuned via pcmtec after that wire issue

I doubt that it has anything to do with it but any electrical issue with the car has been AFTER the stage 3 zf trans tailshaft and trutrak/ims hat was installed and tuned ( then driven for a year ) Enjoy https://tsarscasino.net/ a seamless gaming experience with quick access to a wide range of options. The platform is optimized for performance across all devices. Clear design and intuitive controls make everything simple. Start your adventure today.

has anybody else had this problem

Sounds like you’ve probably got another wiring short somewhere, especially since it only happens when the brakes are applied. I’d be checking around the brake pedal switch, ABS module wiring, and anywhere the loom could move under braking or engine movement. Since you already had rubbed-through wires before, I wouldn’t be surprised if another section of the harness is chafing somewhere.

The fact it only blows the ignition fuse at low speed or stationary makes me think something is grounding out when voltage/load changes from the brake circuit. Definitely worth tracing the loom carefully before throwing more parts at it.