[sedanGen7]

Yeah, I did it - zapped the 100/70AMP main fuse by hooking up the battery backwards - everything went dark, no lights on the dash. The Hazard lights still worked, the brake lights too. I replaced the 100A main fuse, now all the dash lights* come on...but no function from the fuel pump relay

*the green-key immobilizer(?) indicator blinks, then goes out. The yellow Engine indicator blinks, then goes out, dash lights all good, I guess. Key fob functions as normal

The car will start until it runs out of gas due to the fuel pump not getting power. The pump does work - I got in the trunk, tested it, finally, put 12V to it and hot wired it. It pumps and it will pressurize - If I turn the key the car will start.

I had a new Fuel Pump Relay shipped in, Honda OEM, Denso, replaced the original Mitsuba. No difference. (I knew the Mitsuba worked after bench testing it, but had to try new relay)

I jumped the Fuel Relay Socket under dash in cabin, that will charge the pump, pressurizes the lines, and the car will start! I only tried that to see if it would work.

TLDR;
Is there anything other than a bad ECU that will prevent the Fuel Pump Relay (#R2 blue color) from working?

Can I safely hot-wire the relay for a trip to the store 5miles, or at worst a trip the the dealer 75miles? I need to go to the dealer anyway for service. I really need to get to the grocery store now (super rural, no cabs) eeeghads

Could it be a bad fuse box, since I may have zapped it? the 50A fuse is good - all fuses have power and are not broken.

Thanks for any advice . A mechanic did plug in an OBD tester and said there was nothing of note there.

R
'06 Honda Accord 2.4 AT Sedan - great car.

side note: when the car was 2 yeas old, it would randomly blank out, all power lost, all lights lost, engine shuts down, first time at 35mph then a few years later at 60 mph. After coasting 1 mintue it would kick back on all by itself. Total mystery. Ground strap at battery looks good and it only happened twice, I've owned it since new. Anyhoo, always made me wonder.

 

[neil hostetler]

you should follow an oem service manual. the pump runs off of pgm relay 2 which gets power from the pcm. listen if pump runs for 2 seconds after turning key to on position. if the pump doesnt run you can jumper the 12 volt power contacts of pgm-2 after removing this relay. (connector terminals 1 and 2). if the pump now runs the relay is bad. reinstall relay and remove jumper wire

 

[neil hostetler]

also check ALL fuses in the passenger and engine compartment

 

[sedanGen7]

Neil, thanks for the recommendations. If I could get my hands on an OEM ignition schematic that would help. Haven't been able to locate one for the '06 Accord. All fuse and relays, also power at their sockets are functioning. Bottom line question is how many miles/hours can I drive the vehicle while the fuel relay is jumpered/hotwired? (R5 relay under dash). The pump will be on full-time when jumpered at the fuseblock. Does the pump care once the lines are pressurized? The idea is to drive it to the dealer 75+ miles/90minutes. I'll run a trial up to the store but, while sketchy, its where things are, this side of pulling the dash apart and looking for a short. or the ECU is toast at the R5 relay command.

ps. once the gas lines are pressureized, the car runs. With the pump off, there's 15 seconds of engine running, after that no gas. So I'm guessing the pump is basically on full-time in normal operating.

 

[frenzal]

 

[sedanGen7]

frenzal!, many thanks! Would you also have one for the fuel pump electrical system/fuel pump relay in the under dash fuseblock and computer area? Much appreciated,
R

 

[frenzal]

 

[frenzal]

 

[frenzal]

This is all I could find in the manual. Hope it helps you and that it is the right thing (sorry, don't have time to read all, just searching for "fuel pump").

 

[sedanGen7]

frenzal, having those is fantastic, everything I probably need. Certainly sheds light on the system. Many thanks again! Wishing you a peaceful year end. And hopefully not too much snow shoveling.