My Fix For Alternator Lt On After Start-up Until High Revs
Discussion
Disconnect the indicator warning light and run 2 leads from that light to 2 x 5 terminal relays as shown, connecting them to terminal 30 of each relay
Extend the leads that have been disconnected from the indicator warning light and connect them to terminal 87a of each relay (Marked on the diagram "To LH Indicator Lts" and "To RH Indicator Lts")
Leaving the Alternator Light original wiring as is, connect a lead to each side of the alternator light and run those leads to the relays, connect them to terminal 87 of each relay as shown
Run a fused ignition supply to terminal 85 of each relay coil
With a short lead, link together terminal 86 of each relay coil and extend that same lead to a 3rd 5 terminal relay connecting it to terminal 87a
Connect terminal 30 of this same 3rd relay to earth (Return/Ground or whatever else you call it)
At this same 3rd relay, connect coil terminal 85 to earth (Return/Ground or whatever else you call it)
At this same 3rd relay, connect coil terminal 86 with a lead to the fuel pump wire that goes directly to the pump (After the pump control relay)
Someone somewhere has got something wrong with this vehicles alternator warning light circuit, the wattage of the bulb should be 3 Watts or more, higher than 3 watts is not a problem apart from heat from that bulb, lower than 3 watts highers the alternators cut-in speed, I don't think a 3watt bulb is made for the type of warning light that is used but I could be wrong
Carrying out the above modification will solve the high cut-in speed problem.
What the circuit does is connect the indicator warning light directly across the alternator warning light to up the wattage to something in the region of 4.4 Watts when in the ignition on position, once the engine starts and the fuel pump has a permanent supply the earth will be broken from the relays and the LH/RH indicator warning light circuit will be back to standard. Remember to allow a second or 2 for the fuel pump to prime before the relays kick in and the crank the engine, the alternator will now have a low cut-in speed
Extend the leads that have been disconnected from the indicator warning light and connect them to terminal 87a of each relay (Marked on the diagram "To LH Indicator Lts" and "To RH Indicator Lts")
Leaving the Alternator Light original wiring as is, connect a lead to each side of the alternator light and run those leads to the relays, connect them to terminal 87 of each relay as shown
Run a fused ignition supply to terminal 85 of each relay coil
With a short lead, link together terminal 86 of each relay coil and extend that same lead to a 3rd 5 terminal relay connecting it to terminal 87a
Connect terminal 30 of this same 3rd relay to earth (Return/Ground or whatever else you call it)
At this same 3rd relay, connect coil terminal 85 to earth (Return/Ground or whatever else you call it)
At this same 3rd relay, connect coil terminal 86 with a lead to the fuel pump wire that goes directly to the pump (After the pump control relay)
Someone somewhere has got something wrong with this vehicles alternator warning light circuit, the wattage of the bulb should be 3 Watts or more, higher than 3 watts is not a problem apart from heat from that bulb, lower than 3 watts highers the alternators cut-in speed, I don't think a 3watt bulb is made for the type of warning light that is used but I could be wrong
Carrying out the above modification will solve the high cut-in speed problem.
What the circuit does is connect the indicator warning light directly across the alternator warning light to up the wattage to something in the region of 4.4 Watts when in the ignition on position, once the engine starts and the fuel pump has a permanent supply the earth will be broken from the relays and the LH/RH indicator warning light circuit will be back to standard. Remember to allow a second or 2 for the fuel pump to prime before the relays kick in and the crank the engine, the alternator will now have a low cut-in speed
Edited by Penelope Stopit on Friday 12th May 08:08
A bit over the top. Just box it up and send it to Brice they can set it to come in at low rpm.
http://www.brise.co.uk/
Alan
http://www.brise.co.uk/
Alan
Oh thank God for this!
The last 14 years and 50,000 miles have been sheer mental torture, while I have worried endlessly about that warning lamp staying on for 2 seconds more than it would in any normal car. I've even "pushed the envelope" on many occasions, and driven the car 100 yards out of my street early in the morning with the WARNING LIGHT STILL ON (oh yes, I know how to live it on the edge), to avoid blipping the throttle and annoying the non-cogniscenti neighbours...
It has been little comfort, of course, to learn that every other car of the same model does exactly the same thing with no apparent ill-effects. No, what if mine is different and is truly f
ked?
The stress, the sleepless nights, the "anxiety" crease in the seat, all totally unnecessary.
Thank you, thank you, thank you.
The last 14 years and 50,000 miles have been sheer mental torture, while I have worried endlessly about that warning lamp staying on for 2 seconds more than it would in any normal car. I've even "pushed the envelope" on many occasions, and driven the car 100 yards out of my street early in the morning with the WARNING LIGHT STILL ON (oh yes, I know how to live it on the edge), to avoid blipping the throttle and annoying the non-cogniscenti neighbours...
It has been little comfort, of course, to learn that every other car of the same model does exactly the same thing with no apparent ill-effects. No, what if mine is different and is truly f
ked?The stress, the sleepless nights, the "anxiety" crease in the seat, all totally unnecessary.
Thank you, thank you, thank you.
lewdon said:
Hi Phillpot
Sorry to be pedantic but I think the extra bulb needs to be in parallel not series. I am happy to be corrected.
You are correct, added a bulb to mine, and if you position the extra bulb under the dash you get the added bonus of a footwell light. Sorry to be pedantic but I think the extra bulb needs to be in parallel not series. I am happy to be corrected.
Altered mine as I leave home early and didn't want to disturb the neighbour. Then got my first complaint, he overslept!
Rob.
RayTVR said:
I used to have a Delorean which suffered from exactly the same problem.
I found that by adding some additional components I could also make the alternator lamp disappear slightly more quickly.
I found that by adding some additional components I could also make the alternator lamp disappear slightly more quickly.
I always thought that on the DeLorean, the alternator warning light went out when you got to 88 mph?Great Scot
Edited by glenrobbo on Wednesday 18th January 11:36
Barkychoc said:
I think you lot are being a bit mean to a new member thinking about fixes to various issues around the cars.
Don't be frightened off - it's all in jest.
Yes Chris, that's quite true. We're only jealous. We won't bite ( we can't, we've got no teeth left. Except for Phillpot, who's made some out of stainless steel. Don't be frightened off - it's all in jest.
You need to watch him ).Considering on Saturday you said...
Considering the cut-in speed of an alternator is approximately 1000 RPM give or take a bit, think now about the ratio crank pulley size to alternator pulley size, the alternator is going at some good revs even at engine tick-over
I doubt very much that the problem is a standard factory build problem
Good work on coming up with such a comprehansive fix since then. Have you had time to test it yet? Does seem OTT and not checked it for sanity either. I simply put a Jaguar v6 24v in and problem (? Feature) went away..
All the best
Damian S3
Considering the cut-in speed of an alternator is approximately 1000 RPM give or take a bit, think now about the ratio crank pulley size to alternator pulley size, the alternator is going at some good revs even at engine tick-over
I doubt very much that the problem is a standard factory build problem
Good work on coming up with such a comprehansive fix since then. Have you had time to test it yet? Does seem OTT and not checked it for sanity either. I simply put a Jaguar v6 24v in and problem (? Feature) went away..
All the best
Damian S3
A simplified method of my fix would be to use the handbrake warning light switch to trigger the relay's instead of the fuel pump supply
The problem with this method is that the circuit will only work when starting the car with the handbrake on and the indicator warning light wont work when the handbrake is on
The problem with this method is that the circuit will only work when starting the car with the handbrake on and the indicator warning light wont work when the handbrake is on
Edited by Penelope Stopit on Friday 12th May 08:09
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