Relay letdown. Pre emptive replacement?

[NicBowman]

Hi

Having previously said after 40 years and 7 TVRs that I had never been let down, I had to leave my Griff and take the Tesla last week. Battery dead, one week off the trickle charger.

Bought a new battery as a precaution, but measured 0.2 amp current drain. Eventually traced it to the courtesy light relay timer. Pulled it out, back to 0.02 amp. Better.

Thoughts, time to replace relays as a preemptive strike? The two loose ones with the stripe are fuel pump? I think. Any thoughts on what to replace and where to source?

Thanks


Nic
Ps. On the dampers (different thread), still thinking.

[indigochim]

NicBowman said:

Thoughts, time to replace relays as a preemptive strike? The two loose ones with the stripe are fuel pump? I think. Any thoughts on what to replace and where to source?

I've just bought a couple of replacements for mine as the fuel pump was intermittently not priming on turning the key to the 1st click.

These are the ones from the loose connectors. Any way of identifying which is the fuel pump and which is the "Main" relay? I noticed that the blocks they plug into are one Yellow Black and the other Blue.



Part numbers are both partly worn on mine but that's Bosch 0732014112 this is no longer produced so I've bought what Amazon tells me is it's replacement 0986AH0602 although the diagrams on the side suggest that pins 85 and 86 are transposed looking on the Bosch website suggests the pin layouts are the same. I'll be fitting them at the weekend so haven't yet tested them. Amazon link is here Bosch 0986AH0602 £9.75 do your own research to check your happy or I'll try and remember to post results once fitted.

Edited by indigochim on Tuesday 30th May 14:32

[andrewbr]

Plug them into the socket and see if the corresponding function works. Seriously, I chased down a "non operational" fuel pump just to find out I plugged a new relay into the wrong spot...

Those look correct btw, part number from my records is 0332014112 which matches your picture. I got mine from ebay.

[NicBowman]

Hi, thanks. Both the same? This agrees with Motaclan who sell the same for £13.97. TVR tax not too bad! Have brought two from Amazon.

Any more on the main fuse board vulnerable? I would honestly recommend everyone pulls the courtesy light one, who has a TVR because the interior lights stay on!

Nic

[andrewbr]

Both are the same, you can swap them to test if one isn't working (presuming the other is still ok).

[Belle427]

Cooling fans and ignition circuits are worth considering too.

[QBee]

I read somewhere that the two relays are not identical, and that if you use the wrong one it stays open circuit when you turn the ignition off and drains the battery.

Your best hope is that someone who knows comes along and tells you I am talking round objects….or gives a better explanation. In the mean time I will pop outside and photograph my 1999 Chim relays.

[Colin RedGriff]

The two relays lying loose in the harness are the same, but they are slightly different from standard relays (the relays in the fusebox are standard relays) as they have a diode in them to prevent back current.

[QBee]

Cannot get close enough to photo them, as they have been cable tied out of the way.
One is the number quoted above, and has a diagonal pink stripe on the metal case.
The other is completely different and has a circuit diagram on it showing some sort of switching circuit right top.

[glow worm]

Mine in a Chim were identical, Bosch 0332014112 12v 30A made in Spain , replacement item Bosch 26026H (0986AHO602) made in Taiwan , there's a surprise

[phillpot]

Lets clear this up, they are both the same but they are not the same as "standard" relays used to switch horns, rad fan etc.

Silver with red stripe is old, now obsolete.

Current Bosch unit is 0986 AH0 602

[glow worm]

I thought that was what I said

[phillpot]

glow worm said:

I thought that was what I said

just clarifying "any old relay" will not do

[sixor8]

Many moons ago (early 2002 I think it was) my 1995 Chimaera 500 would not start and the RAC chap diagnosed it as the fuel pump relay (he even knew where they were, perhaps they were more knowledgeable then? I digress). He changed it for me, and I was off the 150 miles home on a Friday afternoon, relieved.

Battery completely flat the next day, turned out he'd fitted a standard relay (they even may still carry them) unaware that the connection orientation leaves a current path (I think the lambda heaters?) when the keys are removed. I learnt that at the Lucas wholesalers in Netherton (when they existed!) who supplied the correct one, I fortunately hadn't binned the old one. An open circuit wouldn't draw any current, by definition.

[Belle427]

This a diagram of the relay contacts from the Bosch originals.

[phillpot]

And the current Bosch replacement

[Adrian@]

Given that the diode internally is not correct direction wise, and posts 85/86 are swapped. A@

Part numbers are both partly worn on mine but that's Bosch 0732014112 this is no longer produced so I've bought what Amazon tells me is it's replacement 0986AH0602 although the diagrams on the side suggest that pins 85 and 86 are transposed looking on the Bosch website suggests the pin layouts are the same. I'll be fitting them at the weekend so haven't yet tested them. Amazon link is here Bosch 0986AH0602 £9.75 do your own research to check your happy or I'll try and remember to post results once fitted.
[/quote]

[sixor8]

In the 2 diagrams on the relay cases, one shows the diode before the relay coil and one after, yes. But this shouldn't really be an issue, a diode by design having very little current draw itself.

The fact it allows current flow from 86 to 85 is the main thing and as long as the terminals on the relay go to the correct terminal in the wiring.

[Adrian@]

sixor8 said:

In the 2 diagrams on the relay cases, one shows the diode before the relay coil and one after, yes. But this shouldn't really be an issue, a diode by design having very little current draw itself.

The fact it allows current flow from 86 to 85 is the main thing and as long as the terminals on the relay go to the correct terminal in the wiring.

I cannot say as I have neither my Griff or Chim around me to look at (and I have not purchased a relay either, or even then, going on the diagram I would not of)... I was looking at the flow direction of the diode. Are you saying that this is terminally incorrect on the car (or would be if it were fitted). A@

[NicBowman]

Hi, the diode will function the same in either old or new diagram. It is fitted in the same orientation (flow wise) just the other side of the circuit. So all good.

Nic