Maximum Current Draw

[stuck]

Gent's,

I want to make up a 37 pin ECU extension lead so I can move my ECU, can anybody tell me the max current on any pin please (can't imagine it's much) so I can pick the correct size conductor?

Ta muchly,

Mick.

[zardos]

Probably the maximum current is the injectors and they are usually fused at 7.5A but they have 2 pins.

Looking at current rating of that type of connector, RS list the maximum current carrying capacity as 7.5A e.g. http://uk.rs-online.com/web/p/d-subminiature/2597562/

So 0.5mm2 will the nearest match (11A)

[stuck]

Excellent,

Thanks for that.

[Cynic-al]

The megamanual website gives this guidance

"For the wires from the DB37 connector to the sensors, injectors, etc., use 18 to 20 gauge for all the connections, then bring them to a common 14-12 gauge where appropriate. The only big wires are the ground and the two injector driver pairs, 32-33 and 34-35, all the rest can be 18 gauge all the way out."

http://www.megamanual.com/v22manual/mwire.htm

[muttleyd]

Just working my way through the devils knitting. Currently plumbing in Ms ecu and relay board and notice that edis, idle valve and lambda all need switched feed (not on relay board).

So what's the current draw for edis, Bosch idle valve and lambda sensor?

Or more to the point can I feed all of them via a standard 33amp relay. Was thinking of fusing coils separately from the idle and lambda after the relay.

Wiring still gets me confused though plumbing all this in is making it clearer, am almost enjoying it.

Advice appreciated

[FridgeFreezer]

Muttley - none of those things draws much more than an amp or so, the EDIS is grounding the coils, so the coils themselves may need a more chunky 12v supply and the EDIS needs a GOOD ground wire that can handle the full coil current.

For the 37-pin connector use 1mmsq for the injectors, 0.5mm will do for sensors etc., 0.5mm will do for the grounds if you use LOTS of them (remember the ECU is grounding the injector current) I think I used at least 5 ground wires on mine as the 0.5mm ones are easier to solder to the 37-pin.

[muttleyd]

Thanks Fridge,

So what should be the fuse for the coils. Am sure I read somewhere that they draw 10A under normal running with spikes to 17, but not sure if this is each or for the pair?

As I am using a relay board would you recommend just using the relay board earth or run separate earths from the ecu end of the d37 cable to the battery?