DOPS (Buzzer of doom ) MOD

[AngeloEvs]

In answer to PM for details on converting late vans with DOPS 'buzzer of doom' removed (or not functioning reliably) and wanting to convert to the earlier oil pressure warning system with LED connected directly to the oil pressure switch.
No need to remove the membrane, just carefully lift the DOPS socket from the rear of the speedo housing.

1. If retaining the original LED then fit a resistor of value between 470 ohm and 1.5K in the dops socket as shown. Use a 1/4 W or 1/2 watt as these have thicker leads and will grip into the socket more tightly (avaialble from Maplin, Rapid Electronics, RS, etc and cost a few P.

2. If wanting to upgrade to a Flashing Red Led then purchase a 12v type (clear or diffused) and fit a wire link rather than a resistor.


Simplified schematic of post 86 vans with BOD (note that I have shown LEDs not bulbs for the panel lights as this schematic was constructed as a reference for my Hardwired PCB conversion.

[ringo]

In answer to PM for details on converting late vans with DOPS 'buzzer of doom' removed (or not functioning reliably) and wanting to convert to the earlier oil pressure warning system with LED connected directly to the oil pressure switch.

Whats does this mean Elvis? Will fitting this resistor stop the buzzer but keep the led operation?

I never even new there was a DOPS module....

My BOD is going off all the time so i have had to disconnect the sensor from the alternator so i can drive the van - i have fitted an oil pressure gauge so i know the oil pressure is fine - but i would like the led operation to want me (and the buzzer was very useful i found).

Cheers,

Ringo

[AngeloEvs]

Fitting the resistor (or link if using a 12V LED) connects the oil pressure LED directly to the low oil pressure switch as on earlier vans (pre 86). The DOPS PCB in the speedo can be removed or left in situ but not connected.

I guess some have removed the DOPS due to them being faulty (and expensive) or may be they are just missing, but found that doing so stops the oil pressure warning LED from working. Hence the post.

I have takem mine a stage further by connecting a green LED to the high oil pressure switch and this is usually on all the time (after engine switch on) unless the rpm drops below 1000. I find that more useful than a buzzer of doom and earlier vans manage to survive quite happily without the DOPs.

[ringo]

So if i wanted to fix my buzzer of doom, then a new speedo might do the trick?

Thanks

Ringo

[AngeloEvs]

The DOPS pcb in the speedo can be unclipped and removed easily , no need to change the speedo, Diesel ones are different to petrol so be aware of that if buying s/h. PM me your address as I have a Diesel one you can have for nowt, never tried it though but might be good!

[ringo]

I may well have found my problem - although i could of introduced it today.

One of the tracks on the pcb has been cut (ripped):



I dont think i can fix this track. Applying a soldering iron just seemed to melt it!

According to your schematic Angelo, the track split goes to the 0.3 bar sensor. I suppose i could wire up a direct connection to this sensor (pain in the ass that will be).

Anyway, for now i have just got the whole plug disconnected until i can resolve this...

Thanks for the help (and the DOPS unit) - i will get in touch about that...

Cheers

Ringo

[AngeloEvs]

you might be able to repair it by carefully scraping the plastic covering with the edge of a sharp blade to expose the copper track and then bridge it with the conducting paste used for repairing heated windows. Its expensive but I have a tube that you can try rather than buy one.......see if you can expose the copper track either side of the break and let me know.

[R0B]

like the man said.stuff like this should do it..http://cgi.ebay.co.uk/Electro-Connector ... 0100250453