13 replies to this topic

[tony kenobi]

Hi all, posted a while back saying my mpi wouldnt start, then got it sorted, well its not been going for 3 days now, and im very worried. I replaced the relay that controls the ecu and fuel pump as it seems my pump is not starting up when i turn the key.but this made no difference.

Ive went right along the fuel pump fed and no power, from the pump, to the interia switch, to the multifunctional relay even in the fuse box inside car, so im guessing now the ecu is not sending power to it?? what i have noticed just there now tho, is that one of the connections, just behind the air box, has a brown and slate wire going thru it (fuel pump) looks as if its burnt out, just on that pin! So something along the way has went, but the fuse is still ok. maybe someone can help? The relay that i replaced is doing alot of clicking (as did the original) etc, and ive heard that the car uses this as an immobiliser if something is wrong, would this be what is happening to me?

Would reseting the ecu help? Ive tried the "hit the pedal 5 times in 10 seconds before you turn on" and nothing again. im really quiet concerned, i hope someone has a better knowledge of this type of problem and can maybe help out. thanx all.

[tony kenobi]

so just been out at it for another evening, defo no power getting to fuel pump, everything else is working. its turning ok, trying to start, but the motor isnt kicking in. the multifunctional relay is doing alot of clicking. no power as far as fuse under dash inside. The fuel pump is ok, i tested it from the battery, ive tried reseting the ecu,nothing. Ive checked all my sensors, the ecu earth, everything is clean.

the only thing that stands out, is the connection, just behing the airbox, a black connector into a black connector. It has a brown and grey (slate) wire,which is connected to the fuel pump. I opened the connector up to find that the 2 pins have a small bown mark round them,like a spark mark.there si power getting to everything else on the connector, aprt from this brown and grey wire.this comes from the ecu, so is it the ECU not sending power down to the fuel pump because it has detected a fault? What would have caused this? Has it told something else to shut down?

[GraemeC]

Brown/Slate wires take power from the fuel pump relay in the relay pack through fuse C7 (10 amp) and on to the inertia switch.
The fuel pump relay is triggered by +12V on the white wire going into the relay pack when ignition is on and also triggered by the ECU giving earth continuity on the Black/Purple wire entering the relay pack.

So turn the ignition on and check for a voltage on the Brown/Slate at the relay pack connector. If voltage present pull fuse C7 and check for a voltage on the connections in the fuse box (should get +12V on one contact). If OK replace the fuse and check for +12V at the inertia switch - ie chase the voltage down the line until you lose it!

If no voltage on the brown/slate at the relay pack then check for +12V on the white wire (still with ignition on). If its there then it is either the ECU is not trigging the relay or the relay pack is goosed. If its not there check fuse A4 but to be honest you would lose more than just fuel pumps if that had blown.

You may be able to use a continuity test to see if the Black/Purple is going to ground or, if you are brave, disconnect the ECU and then earth the black/purple and see if the pump fires up.

My gut feeling will be a burnt out wire somwhere along the brown/slate, from what you have said, or the fuel pump relay burnt out. Problem is if you find the burnt out bit whether the cause of it is still present!

[GraemeC]

Also have a read of:
http://www.theminifo...showtopic=46558

[tony kenobi]

ive replaced the relay pack this morning, made no difference. ive no power from the brown and grey wire anywhere (at the relay, fuse box, interia switch ) im getting power everywhere else. checked a4, it fine. it seems like the ecu is not triggering the fuel pump. Or the connections where the wires have burnt a bit (it very small )

When i turn the key, i checked all fuses connected with fuel pump as per haynes manual. Been studing the wiring diagram for fuel system all bloody eve. cant really see what it is! If it the ecu, is that a big job?

[Sprocket]

The fuel pump relay is energised for a few seconds when the ignition switch is turned on, it does not stay energised. It only energises again when there is activity sensed on the crank sensor IE the starter is turning the engine over. Therefore making it difficult to trace the fault.

You say there is burning of wires? this is not normaly a good sign!!

Pull the large plug off the relay pack and with a small flat head screwdriver, remove the white terminal shield. Have a look at these terminals, any sign of burning here could mean a bad connection and maybe your problem. If its the terminal that burnt only then it is a loose connection at that point, it wont neccisaraly take the fuse. it is possible the track on the PCB inside the relay pack has been burnt as well. Also worth noting, the relay packs are not interchangeble trough the rover vehicle range. if there has been a short of the brown slate wire than damage to the relay pack is almost certain

Check the ECU ground piont is in good clean condition.

Have the ECU and relays tested with a service tool. Is the relay clicking sound continious and rapid? It could be that there is an earth leak some where in the wiring but it could be the ECU, unfortunately. Eliminate the wiring first. If its just the odd click when you turn things on then the ECU and relay pack are energising the relays as they should.

This is going to be another one thats going to be difficult to sort with out me actualy looking at it.

It would apear that there are more and more wiring and electrical faults on these cars as time goes by, do remember that the youngest of these cars are getting on for 7 years old.

[tony kenobi]

it sounds like the fuel pump is not getting energised at all. The car turns over, but is not getting fuel. i got the replacement relay from a rover 200, same part number. it clicks when i turn the key and when the fuel pump should be energising. and then clicks again when i turn the ignition off (thats normal i suppose). so i guess the relay is doing its job. the shorted wires where the brown and grey ones, a connector just behind the airbox (you could see the little yellow connector inside had a brown mark around that specific pin)

I checked the ecu ground point, it fine. everything else seems to work in the car (but suppose hard to tell if its not starting lol) but its wierd, no power to the fuel pump, then i checked the interina switch, none either, came back to that dodgy plug, none there (all on the brown and grey wire, everything else had 12v),went back to the relay just as it comes out of it, none there. tried fuse c4, none there. unless its the connection immediatley out of the relay? it cant be the white wire from ignition switch, as everything else is going, or maybe thats wrong?

Edited by tony kenobi, 01 June 2007 - 11:37 PM.

[Sprocket]

Maybe an idea to check the crank sensor

[tony kenobi]

yeah, had a wiggle at it earlier, took it off and it looked ok, tho maybe have a better look in the morning. my engine bay got a little damp last saturday, and this is really from when all this has started happening. a hose came off the bottom of the rad and squirted up, but everything ecu side of the engine was still dry. Oh, also im curious, beside my horn plug, in the smae loom, ive another plug thats just hanging there, always has done, any ideas? has 2 pins on it.

Think ill take the DIS of tomorrow, check the crank sensor,but its really starting to bug me now. took the ecu out this eve for what looked like the first time.the 2 connectors into the bottom where fine tho.

But why would the ecu not send power to the pump? (if thats what its doing?)

[tony kenobi]

ok, so a friend who is an auto electrican came round this morning. he put the new relay in and jumped the pump from the battery, then started the car. So it started,but i knew this already,but the fact the pump wasnt coming on without the jump still wasnt fixed. he said, leave it a while and now it should work. the new relay just needed to start up, now its fine.

also,the burnt pin on the connector, he bypassed crimping on a new wire taking it past the damaged connector. so ive been waiting for it not to work and prove him wrong, but all day its been driving a treat.The relay is behaving and turning the pump on everytime. The redex in the petrol i put in to help the problem earlier in the week is showing its worth and the new coolant while i was at it etc. mini driving like a dream. (must be the fact i missed it over the last week while its been dead)

But with my weeks worth of injection system reading behind me,something i commented on when i got the car has got my attention again. when sitting idle,the engine is as smooth,but head to the end of the exhust and its lumpy. Now ive been told this is normal on a mini. But its just like spitting the odd time and popping. and when it does this, the engine ever so slightly moves.now with all my reading, would it be a sensor causing this, adding more fuel to the system causing it to be lumpy?

I know my solution isnt exactly what others with the problem are looking to hear, but its going, i cant fault it at all.

[tony kenobi]

but if one thing it all taught me to check those sensors if you've an injection. and start to know them all,what they do and how they can play up. I was a worried man last nite. the solution is not to throw money at it, hoping to fix it, thankfully, i only spent £5 on the relay and my mate was free (at 9.30 this morn,lol)

My fingers are crossed that the problem will go away,i hope anyone else with a similar prob has the same luck i had.

[Dev]

glad you got it sorted

[kerguelair]

glad you got it sorted

Just had the same problem on a rover SPI engine. No power to the fuel pump, everything else worked fine.
Fuse C7 was okay, inertia switch too.
Disconnected the battery, pushed the accelerator pedal (10 times) to drain
residual currents in the ECU, waited to the next day and changed the relay pack (ref : YWB10022 for SPi and
YWB100970 for MPi).
Left the ignition on for 10 sec to allow electronics to stabilise and re-initialise, and the car started smoothly !


Relay pack was cracked, allowing water to enter it. It is indeed installed very near the hood...

[redhotmini]

iirc the unused plug on the wiring loom near the horn is to do with the air conditioning motor thats found on japanese spec minis. rover would have made 1 wiring loom that covers all models, i.e. my cooper doesnt have fog lights, just the 2 driving lights in front of the grill, yet the plugs are there for the fogs, and there is a plug for the extra fog light switch inside.