classic kev
Well-Known Member
Hold up chaps. Both the main EFI and fuel pump relays have diodes in them so do replace on a like for like basis. I know in theory an "ordinary" 30 amp changeover relay should do it but the diode is there to protect against back emf iirc.
HTH
HTH
As I said, it should be replaced for another tin top!
As Above, if it has a diode in it, you will have to test the relay with the Pos and Neg in the right orientation...
Usually it is 85 to Positive and 86 to Negative....
Try the test with the pos and neg one way round then the other and see if you get a result!
Ah ok, so the tin top relays are different to other 30a relays.
Is that why they are so expensive?
I searched online with the Bosch part number, and it comes up with some Bosch items in brown plastic too? Would they be the same, but just a later design (cheaper to make with tin?) I assume so if they share the same p/n?
Is that why they are so expensive?
I searched online with the Bosch part number, and it comes up with some Bosch items in brown plastic too? Would they be the same, but just a later design (cheaper to make with tin?) I assume so if they share the same p/n?
Most likely if it has the same Part Number...
Am glad you mentioned that!
So one relay works with + 86 & earth 85!, but not the other way round.
And the other relay is totally dead.
Any idea common way they dye? Looked inside and nothing looks obviously burned out/ damaged.
The coil usually gives up the ghost, and sometimes with no external proof...
Maybe I had the pin orientation wrong, but aslong as you get a reuslt one way and not the other, it means it is working...
As for the second one that nots works either way, Time to replace it I think!
EDIT: Yep relooked at the schematic ... 86 is Positive, 85 is Negative on a Diode Relay
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good suggestion, but my soldering is "adequate" at best. so think i will seek out the recommended new item.
was just curious really. as electronics are not my strong point, but always trying to learn why things happens. though i find it easier to grasp when i can actually "see" the damage/ why its had it.
looking online for a new relay, unless anyone has one for sale???
I can confirm the car is running again. Brand New Bosch relay fitted just now, not tin top but the same part number.
Thanks for all the help and advice from everyone.
Non stop learning curve this motoring lark!
I now know how to test relays, and have just bought a proper test light too!
Thanks for all the help and advice from everyone.
Non stop learning curve this motoring lark!
I now know how to test relays, and have just bought a proper test light too!
i think i have been fairly lucking, as have not really had many starting issues on this car in the 12yrs i have owned it. only flat battery problems which was traced to a faulty battery, and some misfiring in winter only.
but this is the best way to learn, by sorting problems. only way to gain new skills. thanks to the forum
but this is the best way to learn, by sorting problems. only way to gain new skills. thanks to the forum
