Prius Fuse Box Plate - Doesnt Allow Car To Start

[rajeshsubra]

Hi all,

After 3.5 years of impeccable service, my Prius has finally given me a first major problem. I was away on holiday for 10 days, and coming back (last week), the car just wouldnt start.

Since I have the Club Toyota breakdown cover, called up AA, who sent a local garage guy to look at it...he figured that the Battery was flat and jump charged it...but no avail... He then found that a couple of fuses (under the bonnet) were blown, and replaced it...but no luck.

The next day, AA sent their own guy to look at it. After 2 hours of trying everything (removing Battery from the boot etc.), he finally figured that there was a broken connection in the fuse box in the bonnet (see photo attached).

Basically, one of the side plates in the fuse box has a small break in it....Dunno how this happened, perhaps when the garage guy jump started it wrongly? Anyway, the AA guy temprarily connected it, and voila, the car would start! But he wasnt able to do anything to keep the connection (tried soldering or wedging a couple of fuses, but they always got blown)

In any case, do any of you have an idea of how to solve it? Is it possible to get just the right side plate replaced? Do I need to get the full fuse box replaced? Better to do it from Toyota service (I got to Jemca Kingston) or better to buy the part and get someone to fix it... (the AA guy?).

Please help...!

Thanks,

Rajesh

[Grumpy Cabbie]

Sounds like somebody has jumped the car wrong!

The Prius is different to a 'normal' car in that the 12v Battery is much smaller (both in size and power). The reason is that it only has to power up a couple computers which then use the large HV Battery to start the engine. A normal car 12v Battery has to be able to turn over the engine with the starter motor at -15c or lower and hence it is more powerful.

If the person who attempted to jump start the Prius didn't know what they were doing they will a, if you're lucky have just blown the large fuse or b, if you're unlucky they'll have blown the fuse and fried most of the cars electronics!

You must be extra careful jumping a Prius;

You MUST NOT get the jump cables the wrong way round or short them.

You MUST NOT rev the engine of the car doing the jumping as this will put way too much load into the small Prius 12v battery.

You MUST NOT jump any car FROM the Prius as the load starting the 'dead' car will destroy the Prius 12v (and probably the inverter too).

I know this is a case of shutting the stable door after the horse has bolted, but the above will be in your Prius manual.

Hope you get things resolved.

[rajeshsubra]

Thanks.... The AA guy also suspected that the other garage guy nominated by AA may have jumped it wrong...

I figured out that the part in contention that needs to be replaced is the Block Assembly, fusible link block. Toyota is quoting around £70 to order a new part and around £120 for labour to replace it...But hopefully no further damage has been done and nothing else has been fried....

Will call up AA and see what my options are.

Thanks,

Raj

[timberwolf]

I thought the Fusible Link Block was in the luggage compartment at the rear of the car i.e. I'm sure it isn't the fuse box in the engine compartment.

Sorry, your photo wasn't clear or even detailed enough to see where you say it is broken.

I took a photo of my engine compartment fuse box around the jump start point and wiring harness point (I think that is what the nut part might be referred to as).

[Chris Dance]

You should only start the Prius via the connection in the engine compartment not at the Battery terminals in the boot. Sounds as if the local garage guy got it wrong???? I would think the AA are responsible for the necessary repair damage. (Local non Toyota garages do not understand the Prius.) The AA should know the correct procedure for starting. It sounds as if your 12V Battery went flat. The life of the 12v Battery is about 3-4 years I am told by my dealer. I did not close my boot correctly on my previous Gen 2. At that time Club Toyota used the RAC and the RAC chap who came knew all about the Prius starting procedure. He said he had training on how to start a Prius.

[timberwolf]

The only reason for the Jump Start point is because it is difficult to open the rear hatch without power, but there is a risk with using the Jump Start point - being that if the 12V Battery short circuits when it fails then it could take as much current as the donor power source is willing to give...that is up until a 100 Amp fuse blows in the Prius. If you charge the 12V Battery from the battery's terminals you obviously want blow any fuses although I suppose the Battery could go bang if the source was not current limited.

Here's the photo that I took during a brief period of sunshine today, The image is of my Gen 2 Jump Start point (on the left), so the OP can compare it with their broken one, the red plastic at the top of the image is the hinge of the door that has been swung open to reveal the jump start point and the nut securing the wiring harness is in the middle.

[rajeshsubra]

Thanks guys, am attaching some more pics - could you check and tell me what part do you think this is? and Do i replace the whole thing? Photo 1 and 2 shows which part I am talking about, and photo 3 shows the nature of the break....

BTW, checked with AA claims to complain about their sub contractor, seems they will only address any claim once an investigation is done by a garage of my choice.

So looks like my only option is now to tow the car to a Toyota service station and have a look at it.

[Peter Sale]

That doesn't look like the sort of part that should crack and from the last picture looks more like a fusible link that has been 'cooked'.

I was going to suggest asking on the Prius Chat forum and someone like Patrick Wong would advise but then found this article on there:

http://priuschat.com/forums/gen-ii-prius-modifications/75224-100amp-fuse.html

Looking on Google before I found this I agree with the earlier poster that there is a fusible link by the 12v Battery in the boot.

Someone is breaking a Prius on eBay and it might be a cheaper source of the part but I would want to know why that link has gone. Either the repair man did something wrong or there is a big problem somewhere. Being older and wiser I have been far too close to too many bangs an flashes !!.

Best of luck with it, let us know how you go on.

Peter

[dwilson]

Sounds like somebody has jumped the car wrong!

The Prius is different to a 'normal' car in that the 12v battery is much smaller (both in size and power). The reason is that it only has to power up a couple computers which then use the large HV battery to start the engine. A normal car 12v battery has to be able to turn over the engine with the starter motor at -15c or lower and hence it is more powerful.

If the person who attempted to jump start the Prius didn't know what they were doing they will a, if you're lucky have just blown the large fuse or b, if you're unlucky they'll have blown the fuse and fried most of the cars electronics!

You must be extra careful jumping a Prius;

You MUST NOT get the jump cables the wrong way round or short them.

You MUST NOT rev the engine of the car doing the jumping as this will put way too much load into the small Prius 12v battery.

You MUST NOT jump any car FROM the Prius as the load starting the 'dead' car will destroy the Prius 12v (and probably the inverter too).

I know this is a case of shutting the stable door after the horse has bolted, but the above will be in your Prius manual.

Hope you get things resolved.

This is worrying me !

At some point my 12V Battery will need replacing but I probably will not get any warning so will be left with a stranded car. With normal cars I would call the AA or RAC ....

Is the problem of AA etc not jumping a Prius correctly a common problem, or have others had better experiences? I don't fancy my car being ruined just because of a flat Battery!

David

[Chris Dance]

When my Battery on my previous Gen 2 was flat. I rang club Toyota and asked them for assurance that the RAC chap would know how to start the Prius. They assured me all would be OK and when the RAC man came he was very knowledgeable about the car. Since Club Toyota changed to the AA I have not needed assistance. It would be hoped the AA know about the Prius. The problem arises if some breakdown firm who know nothing about a Prius are sent out on behalf of the AA. I think Club Toyota and the AA need to know about this issue ASAP.

[bobm]

I had a flat Battery when left car at hotel for 10 days when on holiday, the Toyota guys called out a local garage, he arrived with a Battery charger...which was flat......he didn't know the procedure for restarting in anyway.. I suggested he went to get a charged Battery charger but he insisted it would be better to transport me to my home...well it was on a low loader and 130 miles..........I reported the matter to the Toyota people...which I considered was a total waste of money for them to send this 'garage'.......had no response from Toyota so don't know the result..needless to say it didn't cost me...

[Jan&tone]

The AA/club Toyota bought my Gen2 home from Norfolk last year after my heart attack.No problems with them, the AA guy obviously knew what he was about even just to get it on the back of the trailer!

[dwilson]

When my battery on my previous Gen 2 was flat. I rang club Toyota and asked them for assurance that the RAC chap would know how to start the Prius. They assured me all would be OK and when the RAC man came he was very knowledgeable about the car. Since Club Toyota changed to the AA I have not needed assistance. It would be hoped the AA know about the Prius. The problem arises if some breakdown firm who know nothing about a Prius are sent out on behalf of the AA. I think Club Toyota and the AA need to know about this issue ASAP.

Thanks for the reply. I don't like the sound of a breakdown firm sent on behalf of AA !

I have RAC membership for my wife and daughter - think I will join RAC rather than AA next time!

David

[Chris Dance]

The AA should know all about the Prius and the starting procedure. Club Toyota should ensure only qualified AA mechanics are sent out to a Prius and other Hi Tech cars. I am thinking of contacting Club Toyota about the fact that some local garage bloke may come to your aid instead of an AA trained guy.

[Grumpy Cabbie]

I didn't realise the AA used anyone other than their own people. That's one of the reasons I went to them from National Breakdown - who used any old tom ***** or harry from the local garage.

[johalareewi]

I didn't realise the AA used anyone other than their own people. That's one of the reasons I went to them from National Breakdown - who used any old tom ***** or harry from the local garage.

When i had AA cover, I have had the AA sub contract to a local garage a few times.

I also had to call club toyota for the Prius when I couldn't get the wheel off to change to the spare. They called out an independant tyre specialist (not an AA van man). Luckily he knew how to get stuck wheels off of a Prius

[rajeshsubra]

Thanks all...

The AA is sending someone to recover the car to a Toyota Service station tomorrow, ehen they'll diagnose and replace the errant part... Its going to cost me, but based on what the AA claims department said, if Toyota's diagnosis supports it, then hopefully AA will pay...

Will keep you posted on what happened.

Cheers

Raj