Audio Amplifier 12V

The audio amplifier located in the frunk has a 12V line continuous power and another power line that is turned on from the ignition switch. I do not know how this line receives power since there is only one fuse (7.5A) and no other for the amplifier.. Is the 10A fuse on the front radio power the amp?

2005 GT. I have been enjoying my new radio Ben/Hur conversion, that's where you replace the entire infotainment system. But...I have a problem. Shut the car down, started it up, whole center console was dead. Blown fuse on the fuse box, blown fuse on the back of the infotainment replacement, whole thing dead. Got a replacement unit, two weeks later, same thing. The car shuts down with it working, when it starts up the next time, everything is dead. I can't figure out what would be blowing the fuses and system in such a strong fashion. Obviously, it could be bad manufacturing, but twice after working for a while makes me think it might be an electrical gremlin. What about if the key is turned to the left? Does that do anything that could spike voltage? There are voltage regulators online that I can buy for $25, this seems to be a good idea, but I'm curious about the experts, is this a Bentley thing? Is there a workaround?

There should be a brown or blue wire from your stereo to the amp that provides the power when the ignition is turned on.

The only variable I see is the radio/amp install. Which fuse is blowing? The one for the Ben HUR? The main for the car? For the amp they should have grabbed all the power from the back. Do you know if they ran RCA’s or used hi/low converters? I would have then do a visual check on their connecting work for your head unit. Hopefully they soldered everything. I haven’t experienced this with my radio /Ben H.U.R. Also don’t rule out the radio having a problem. I’ve seen that a time or two in my Circuit City days 🙄 I’m going up there tomorrow to get a quote on the work I want done. I can see how they would run everything and maybe that’s the same way they installed yours. I’ll let you know if you don’t beat me up there or call them before I get there.

Those are all good questions. The fuses that blew were the one in the dash for the infotainment and the one on the back of the Ben Hur, so two fuses blew. When the new Ben Hur was installed, they put in a relay off of a different power source to isolate it, thinking that maybe the Ben Hur and radio were too much of a power draw, this didn't make a difference. And was weird, because it powered up as soon as the key was put in the ignition. It shouldn't have anything to do with the amp, we left the car's power amp alone, since it drives the motion-sensor beeps. It's plenty loud, especially with the new subwoofer so that wasn't a bad call. Also, the Ben Hur didn't fail when the radio was working, it failed either when the car was shut down, or when it was started. The Nav-TV people are dissecting the first blown Ben Hur this week, the second is still in the car. While it's possible that the installer's craftsmanship could have caused this, I can't figure out how one ends up with a short? Is the positive hitting the ground on the Ben Hur somewhere? I guess it could be the radio, since the radio itself draws it's power from the Ben Hur...maybe when it starts up it does something? But the radio worked fine in the second Ben Hur, if it was drawing too much current, it would have blown the second as soon as it started up? Hmm. Maybe it is the radio. It's not the power amp or current draw from the speakers, that's on a different circuit. My car is in the shop getting its wing fixed and the Bentley 65,000 mile service.

Quotes source post: 4798806

Quote: Ohh ok. I thought you also installed an aftermarket amp too. Didn’t know the factory had enough “umph” to put a 8 inch sub. I’m taking my radio out tomorrow to clean it up a little with some Tesa tape. Let me know if you need any pictures or something with the wiring. Well I hope once it’s out the shop you get it sorted out. Who are you using for your 65,000 mile service (please don’t say Bentley Downers Grove) 😂

You're right about the sub, that's on it's own amp, but is wired in the trunk, not powered by the Alpine, so I don't know how it could affect the Ben Hur. I have my service done (inconveniently) at Fluid Motor Union http://www.fluidmotorunion.com/ out in Naperville, they don't do Bentleys exclusively, but I like them, the woman that coordinates everything is all about customer service, she finds Audi/VW parts to substitute, she hand-delivered my car when I needed it but we had a date mix-up, so that was cool. Their shop is filled with exotics, their reviews are outstanding, so I figured, go where the guys who know go. I still haven't tried a Bentley dealer, although who knows? I might be pleasantly surprised. I have one about two miles away. Funny: when I dropped my car off (check engine light for the below code) I got gas, a Lamborghini was getting gas next to me. Later, I saw a Lamborghini parked in the Fluidmotor parking lot, then watched a lamborghini speed down the street. I asked the guy in the detail shop (next door, I'm doing a $250 wax, we'll see if it was worth it), "What's with the damn Lamborghini infestation?"

Hi British - I go to Fluid Motor Union as well - really like them. Haven't brought my Bentley there yet but they've seen my Phaeton a couple of times. Last week they had a Gen 1 Continental on their lot - was that yours? IIRC that one had a Ben Hur installed....

I like them. I don't know if they're better than the Bentley dealer, I have to get a second key (for $1,000) and they were pretty smug about the price. That's probably my car you saw, it's blue with a tan interior without a scratch anywhere on it. I have no idea how the previous owner got to 66,000 miles without even a ding on it. I know it was garage kept and I don't think it ever saw rain or snow. I've had a couple of nuisances, I replaced the third brake light, I replaced the thermostat and when they had all the stuff apart they recommended new plugs, can't argue with that, so I did 12 new plugs too. I wish the Ben Hur didn't keep blowing up. I'm kind of bummed that it's out in the lot, I don't think this car has sat outside...ever. I saw a Phaeton on Ebay, it was oddly inexpensive, the owner was funny, "If you don't know what this is, don't bid on it."

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Quote: Hello British ... Not seen you around hope all is well Whats up with the BenHur, Ive not know one blow up & defo not twice, its not the BenHur something else is going on as you say in the electrical side of it, Have the guys who installed it checked all the connections they made to the system you had installed I know the chaps who designed the BenHur I'll give them a call today see what info I can get for you ... Before I switched from using the BenHur to the radio for audio controls, I as you was using the BenHur without any issues, explain you mentioned in your post "the power is drawn from the BenHur" what do you mean. If you can take a pic or 2 of the wiring I'll have a look how your installers have wired this up ...

Car's in the shop for something else, so I can't send pics, but I wish I had thought of taking some when it was apart, you'd be able to see whether you liked the quality of the work or not. I keep going through the troubleshooting in my head; if the Ben Hur unit blew both its fuse as well as the car's fuse, then the current draw had to come from the Ben Hur unit. The Ben hur unit feeds an Alpine radio. I have a backup camera, but I think that is powered separately, because I asked it to always be powered on to eliminate lag when I shifted into reverse, I read that somewhere. So what is making the Ben Hur draw so much current it blows two fuses and internally self-destructs? Replacing the fuses, it blows them immediately again. The Alpine radio doesn't blow fuses, it was moved to the new Ben Hur and it worked fine. I'm leaning toward some sort of weird power thing during start, or a Ben Hur factory flaw that leads to an internal short. If it was the Alpine shorting, it wouldn't work, same with backup camera, both work fine. I wonder what they're finding as they take the first dead unit apart (second dead unit is still in the car). Oh, and when I say, "Power is drawn from the Ben Hur, I thought the radio was hooked up to the infotainment power? I could be wrong.

Had a very interesting chat with 1 of the chaps at BenHur, these are he's words " in all my time not one BenHur has failed but for 2 to fail in one vehicle then the installers needs to look at the work they have carried out". British read my post I've just done ( steering wheel conversion) you do realise the BenHur only uses 1 rca, for in-put & out-put to the stock amp ... you are losing one channel. so basically the sound is going into the BenHur as mono & then going into the stock amp as mono, then the stock amp sorts out the sound & sends it to all the speakers, but your only hearing mono sound ... the issue with the blow outs on the fuses is a wiring issue 100% this can only be an install error its nothing to do with firmware or any kind of problem with you head unit or the BenHur ... power supplied to the amp is from the the fuse box under the steering wheel fuse 1, 40A. the head unit is fuse 17, 10A which the BenHur also takes its power. BenHur fuse 10A ...

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Quote: The BenHur shouldn't be growing much power as its not a power source for anything but itself, its only a electronic device that controls other equipment, the other equipment has there own power supply, so no its not the BenHur mate its something to do with the wiring ... I'm dam curtain of it ...

I can't argue; you know what you're talking about but what wiring could cause this? Sending positive to the negative terminal of the Ben Hur? Other way around?

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Quote: I cant say my friend without seeing what your people have done, see if you can get some pics & I'll happily look at it ... Im feel for you after all that time you spent on the system & the money you spent on it & you have issues ... so sorry ... If you were in the UK id drive to you ...

I just thought of something, ask your installers what have they done with the second rca that comes out of the head unit You have a sub which is powered directly from the head unit ... Yes ? ... Has this got its own amp or is it powered by the stock amp, if so how have they done this ...

I do know the circuit board is a lil “ehhh” on the Ben Hur...and that power goes into it and back out via this board. IF the wiring checks out, I would look at the power going into it and coming out. The solder points might not be so solid. Just my 2 cents

Quotes source post: 4798926

Quote: TJ ... what soldering is there, the BenHur has all the looms that wire direct onto all the other wiring including the head unit, unless they chopped wires which I find difficult to understand ...

Quotes source post: 4798932

Quote: If you open it up, I’m sure where the power comes in it ties into the the circuit board to power it up. Atleast from the radios and amps I had to re-solder. I just took my radio out. It looks like they use the factory plug to power up the Ben HUR. Then use the Ben HUR to power up the radio. Just maybe they should have used a pigtail, use that to go straight from the factory to power up the Ben HUR and the radio. The harness I have circled, goes from the unit to your radio. They could have bypassed that so now the unit really has nothing to do with the radio as far as power goes. Every manufacturer has a product failure percentage. Maybe British just got two that was made by Fred on a Friday right before closing or that Monday after a weekend of bar hopping 🤭😂🤣

This Thread ... British, read my post & ask your installers, Im very curious to how your systems been wired up ...

Ive given this a long hard think !!! why is the BenHur burning out, not just once but twice. This is my theory ... Your installers have used 1 set of RCA's to connect to the BenHur which then feed sound to the stock amp which is fine as long as you're happy missing that other channel. Now how have they connected the SUB, I think they've used the other set of RCA's & ran that through the BenHur which is over loading the BehHur & burning out, due to the BenHur using the same power circuit as the head unit both units fail due to the fuse blowout, or they've used the SUB out from the head unit & ran that through the BenHur still causing it to burnout, Its impossible to burnout 2 units in such a short period on one car, I cant see any other way they've connected the SUB. I may be totally wrong & they have used an after market amp to run the SUB, you haven mentioned that tho, then it comes down to wiring (power) error, but that shouldn't burnout the unit just blow the fuse/s. Take some pics & ask your guys how have they installed the new system ...