More electrical gremlins... Code 245

[SergSC]

Seems the car is going through a "to break" list. Every couple of weeks something new.

I have already done a forum search which suggest either a failing diode pack on the alternator or a sticking relay.
But I want to list the symptoms here in case one of them points to something with more certainty.

It started yesterday when I got in car and noticed the dash is already On, it complains of heater flap and power supply errors.
I turned the key On/Off a few times, but the result is always the same, dash begins shutdown but returns to main screen as soon as its done.

I had to do a 2 hour drive so hoped it would snap out of it, and it did thankfully switch Off normally when I got back home. I thought great, maybe I'll have charge in the battery in the morning and it was just a glitch, but no... in the middle of the night the alarm goes, queue mad scramble to get dressed, find keys and run down to deactivate the alarm. When I get there the dash is On again. Battery voltage was showing normal at 12V with ignition Off.

So this morning it was still On. I drove it for half hour and switch Off but this time the dash goes Off then about a minute later flickers back On. Nothing I can do about it so I leave it. The alarm starts again after a couple hours. Battery voltage is still reading 12V, I take it from this that the dash being On isn't using too much juice... I do another drive to make sure the battery is charged up but later when I switch Off the whole dash goes mental, switching On and Off very rapidly, needles darting up and down, and a clicking sound from the fuse board... its the r53 brown relay (fuel pump) clicking like mad. Switching On the ignition stops the craziness. After a few more On/Off the dash shutsdown... pheww... I then take out the relay. Dash is still Off.

If the dash stays Off does this mean I almost certainly have a dud brown relay? I suppose the next step in diagnosis is to try taking it out when the dash refuses to go Off.

Cheers
S

[shep1001]

When my alternator went and the dash stayed on, I could switch it off by pressing the brake pedal. The alternator also used to feel warm even though it should have been cold as the car had not run.

Shep

[SergSC]

Thanks Shep, I will feel the alternator when it starts acting up again.

iirc reading right a dodgy 100a fuse may also cause such weirdness. I have a 125a backup so I'll try replacing that first if the alternator is cool to touch.

[shep1001]

SergSC said:

Thanks Shep, I will feel the alternator when it starts acting up again.

iirc reading right a dodgy 100a fuse may also cause such weirdness. I have a 125a backup so I'll try replacing that first if the alternator is cool to touch.

It can, if you are going to the effort of taking the air box out to get to the fuse, change it regardless of it looking ok. They fracture internally which is hard to check. For the sake of £2 just change it.

Shep

[SergSC]

Car is completely back to normal again probably all by itself. Alternator was stone cold in the morning.

When it was raining heavily there were some droplets on the inside of winscreen, today I checked windscreen seal and it is very loose in that area, I can lift it with no effort...
Perhaps the whole episode might have been caused due to water ingress on the bottom of windscreen on drivers side behind the pod, possibly getting into electronics behind there. recomendations on how to deal with that would be very appreciated.
Even if it isnt what caused it I must still fix this problem.

It could also be back to normal because when troubleshooting I disconnected the heater/fan plug under the dash on passenger side footwell (the thing with a couple large capacitors) and forgot to plug back in. If the problem reapears upon reconnecting I'll know what it is. Ties in with another symptom I forgot to mention.... a rumble sound from the heater motor area (despite heater and fan Off at the dials) when key in On position, which is what led me to unplug it. At the time the dash was doing the mental rapid On/Off thing.

Then again I guess water getting into places it shouldnt can cause all sorts of things. When the imobiliser died the weather was also very wet... any other obvious places aside from windscreen that can let it water?
I'd rather take preventative measures...

Oh well I'll get to the bottom of it eventually, think step one is to water proof leccy bits...

[Lone Star]

Let me know how you get on because I'm also getting water in the same place as you. The difference being, it results in my front and rear side lights and the amber Led display next to the rear fog light switch coming on. I am sure its water getting in from behind the rubber strip that surrounds the windscreen. I know this because the other day when I was washing the car. I noticed 2 tiny trickles of water running down the inside of the windscreen. And this was more or less in the same place where the rubber surround is loose. I have tried sticking it back down with a silicon sealant. But I've had only partial success.

[sidpinup]

I had a similar problem in my Tamora and it was water getting in the side of the windscreen and running along the inside edge and dripping onto the fuse card. I pulled off the seal, treated the rust and re sealed using lots of sealant. It solved the issue but I had to have a new fuse card so cost a few quid to fix.

[SergSC]

sidpinup said:

I had a similar problem in my Tamora and it was water getting in the side of the windscreen and running along the inside edge and dripping onto the fuse card. I pulled off the seal, treated the rust and re sealed using lots of sealant. It solved the issue but I had to have a new fuse card so cost a few quid to fix.

Did you reuse the seal? also what rust treatment and sealant products did you use?
I guess the rust comes from a crappy metal frame that the windscreen sits on?

My windscreen rubber seal wrinkles on the top corners, leaving a couple holes where water can probably get into. I have yet to see a tvr without those though... perhaps I could get it round neatly with the help of a heat gun.

Think the fuse car is still ok but I'll try to get it out and give it a good clean...

Thanks
S

[sidpinup]

SergSC said:

sidpinup said:

I had a similar problem in my Tamora and it was water getting in the side of the windscreen and running along the inside edge and dripping onto the fuse card. I pulled off the seal, treated the rust and re sealed using lots of sealant. It solved the issue but I had to have a new fuse card so cost a few quid to fix.

Did you reuse the seal? also what rust treatment and sealant products did you use?
I guess the rust comes from a crappy metal frame that the windscreen sits on?

My windscreen rubber seal wrinkles on the top corners, leaving a couple holes where water can probably get into. I have yet to see a tvr without those though... perhaps I could get it round neatly with the help of a heat gun.

Think the fuse car is still ok but I'll try to get it out and give it a good clean...

Thanks
S

I did re use the seal, it actually came away cleanly so just got rid of the rust in the groove and a wipe with some cleaner got it looking like it would make a good seal. I just used Krust to treat the rust as I had some. I figured that a very good application of sealant would keep it dry. I found that the relays, because they sit upside down filled with moisture and funny things happened like lights staying on.

[SergSC]

Cool, would this suitable sealant?

http://www.amazon.co.uk/Sika-Sikaflex-Polyurythane... be a

or

http://www.amazon.co.uk/Tiger-Seal-TIG-NB-Polyuret...

Thanks
S

[SergSC]

nevermind found the thread

[sidpinup]

SergSC said:

nevermind found the thread

Cool, it was a pretty easy job if a little messy and I also did the door and hoop seals at the same time. No leaks so far and the Tam lives outside. Good luck