Relays

Discuss which Sensors work best with these ECUs and share how you are using inputs and outputs
rjwooll
Posts: 81
Joined: Wed Jan 28, 2015 5:42 am
ECU Model: S40 Pro
Distributor: Lotusbits
Firmware Version: 75

Relays

Post by rjwooll »

Are there any specific requirements for relays connected to the S40 Pro? The wiring between my ECU and the fuel pump relay looks like that very thin wire you find in an RS232 cable and similar, so the current can't be huge. I've had a quick look on the website but can't see anything.

The reason for asking is that my fuel pump relay keeps cutting the power to the pump with a 'sizzling' sound. The relay is rated at 40A and I bought a replacement from Maplin at the weekend - this took around 45mins to sizzle rather than the 5 mins or so with the old relay.

My thought is that maybe the signal current is too low for the relay?

Any help greatly appreciated!

Thanks, Richard
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Relays

Post by stevieturbo »

Exactly which wiring are you referring to ?

And the coil inside relays takes a very minimal amount of current to operate.

And who made the wiring loom ?
Rob Stevens
Posts: 1247
Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Relays

Post by Rob Stevens »

Is wiring as per the diagram? as Stevei says the current is tiny going through the relay coil, the main current to the pump is separate, if you want to test the S40 you can do this via 'test injectors coils and auxiliary's' or to test the wiring permanently ground the pin 1.
it shows you on wiring diagram how to wire a relay, ensure the pump is connected to pin 87 on the relay and ground on the -ve side of the pump.
it sounds like its connected wrong.
rjwooll
Posts: 81
Joined: Wed Jan 28, 2015 5:42 am
ECU Model: S40 Pro
Distributor: Lotusbits
Firmware Version: 75

Re: Relays

Post by rjwooll »

I haven't touched the wiring, apart from putting in a more reliable (fused) power feed bypassing the fusebox, and swapping the relay yesterday, since the S40 was fitted by a DTA partner about 2 years ago. The funny thing is that everything was fine until a couple of months ago when I started getting breakdowns due to the fuel pump not working. Then when I replaced the relay yesterday it only took 45 mins for it to sizzle.

Will check the wiring! Thanks for your comments

Richard
PhillipM
Posts: 177
Joined: Tue May 13, 2014 5:30 am
ECU Model: S80 Pro
Distributor: DTA UK
Firmware Version: 73

Re: Relays

Post by PhillipM »

Check the relay socket for corrosion too.
rjwooll
Posts: 81
Joined: Wed Jan 28, 2015 5:42 am
ECU Model: S40 Pro
Distributor: Lotusbits
Firmware Version: 75

Re: Relays

Post by rjwooll »

No progress today, been out at work. However I would like to add that I have had a couple of occasions over the summer when the car has completely died on me. In these cases the whole ECU was dead and I brought it back to life by wiggling the connector block. Is there any history of unreliability with these connectors - the pins are very fine? It may be the case that a poor connection on the fuel pump earth in this block could be the problem. I'll remove it and give it a dose of contact cleaner in any case.

Thanks, Richard
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Relays

Post by stevieturbo »

Exactly what connector are you referring to ? "wiggling a connector block" is a little unspecific.
rjwooll
Posts: 81
Joined: Wed Jan 28, 2015 5:42 am
ECU Model: S40 Pro
Distributor: Lotusbits
Firmware Version: 75

Re: Relays

Post by rjwooll »

stevieturbo wrote:Exactly what connector are you referring to ? "wiggling a connector block" is a little unspecific.
It's the main multi-pin connector block on the S40 as shown on the wiring diagram - there is only one!

Thanks, Richard
PhillipM
Posts: 177
Joined: Tue May 13, 2014 5:30 am
ECU Model: S80 Pro
Distributor: DTA UK
Firmware Version: 73

Re: Relays

Post by PhillipM »

The connectors are used all over in various industrial and other designs, they're very well proven and documented. If you have an issue it's much more likely that it's a crimping or loom building issue.
stevieturbo
Posts: 3577
Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Relays

Post by stevieturbo »

rjwooll wrote:
stevieturbo wrote:Exactly what connector are you referring to ? "wiggling a connector block" is a little unspecific.
It's the main multi-pin connector block on the S40 as shown on the wiring diagram - there is only one!

Thanks, Richard
You didnt specify the ecu connector, just a "connector block" which there can be many on wiring looms/cars

As Philip says, the type of connector used is OEM quality and used worldwide on OEM vehicles and many aftermarket ecu's. Quality is definitely not an issue...but quality of crimp/wiring itself will be down to whoever made the look, and of course what sort of life it has had in the vehicle or how it was treated by installer etc.
Post Reply