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Discussion Starter #1 (Edited)
Hi all,

Fitted brand new vanos board to bank 1, started car and got rough idle and codes:

43 "Intake valve vanos advance valve cyl 1-4"

48 "Intake valve vanos retard valve cyl 1-4"

b8 "Intake cam vanos position control 1-4"

a brand new board, what the?

The story:

Did vanos maintenance with instructions from all the threads on here. Had no prior codes, but symptoms of slight stutter on only light throttle from slightly below 2000 rpm, ok from about 2300rpm onwards.

Had runs against another member starting in 2nd gear rolling, and took a second to get going, whilst he sprinted away. Drove his car and it felt much more sprightly at lower rpm on light throttle, thought at 14 years and 144,000km time for vanos maint.

Managed to damage yellow wire on bank 2 in the removal process, see pic ,then 2 movs fell out whilst cleaning bank 1, and lost one. Electronics store could not identify the movs.
Wanted to get going for xmas road trip, had a brand new board I was saving for a rainy day, so I fitted that to bank 1.

Fixed wire on bank 2, did cleaning process on bank 2,fitted up new orings and gaskets, install both boards, the brand new one on bank 1.

Rough idle and the codes! cleared and re checked again, yep they come straight back, even without starting up, the 43 and 48 codes set.

Removed the new board from bank 1, noticed that the little biscuit board on the solenoid is sitting at quite an angle compared to the old. could it be shorting out on the cover?

Took it to auto elec repair shop, along with the old board, he's going to try and source the movs to fix the old one, meanwhile i want to get on the road. They checked the new board with the cover being pressed over it, and no shorts.

At this point i decided take the movs out of the new board and put them into the old board, at least it worked before .

Fitted it up and same codes!! Cleared and rechecked, they come straight back.

So, both old and new boards throw same codes, so it has to be in the harness or DME right?

But what are the chances of these failing precisely when you decide to remove the boards for maintenance ??

Spent all day reading every post on these codes,;

Away for xmas , had to take wifes car, back Monday, so try and solve this.

think i will start diagnosis checking board wires to the plug and harness on the board, then the harness end for power to the pins?

then follow that back to DME and check at that end, and the fuse in the DME?

any point swapping boards when 2 boards, a new and the old on bank 1 throw the same codes and symptoms?

IS there something else here i am missing?

Any thoughts would be appreciated,( i have never read a wiring diagram before, so this will be big training wheels for me.)

In last 2 years have fitted mafs, 4 cps, fuel pump, thermostat, o2 sensors etc
 

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Likely you have lost the ground which is common between the noids setting the codes. Broken wire, bent pin?? Using this diagram check the car side of the plug for ground with the key on. So check pin 2 and 5 if one has ground and the other does not start tracing back to the DME. You could jump 2 and 5 on the board and see how the car runs but I suspect you will still get the codes if the wire to 2 is broken.
Vanos Board Schematic_V3.jpg
 

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Discussion Starter #3 (Edited)
Sailor you are right...

Likely you have lost the ground which is common between the noids setting the codes. Broken wire, bent pin?? Using this diagram check the car side of the plug for ground with the key on. So check pin 2 and 5 if one has ground and the other does not start tracing back to the DME. You could jump 2 and 5 on the board and see how the car runs but I suspect you will still get the codes if the wire to 2 is broken.
View attachment 505585
got 4 odd ohms on pins 2 and 5, had trouble getting it on 2, but its there now. Thinking i will pull grommet off vanos side of plug and have a look.

I cant see any damage to the pins. but will look again with a magnifier glass.

The harness goes under plenum, then out the rear of engine and crosses to the DME correct?

Where could one check the harness next? Any pointers for a direction from here would be much appreciated.

Where would we be without this board to turn to???
 

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Discussion Starter #4
Put back together and started it up, for a second it was smooth, then changed into rough idle and mild shaking of the car, exhaust sound rough. switched it off.

Checked codes and cleared, start up and stop again, check codes, still got 43, 48, 8b. Checked vanos plug on engine side again, now i get 12-16 ohms on both pins 2 and 5, the grounds.

Thats not right is it?
 

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No you should have no resistance I think. Looking at WDS the ground should be straight to ground so little or no resistance. You could try jumping a wire to ground. If you are getting the same on pin 5 you should have exhaust cam problems also. I suppose you could have a short also assuming a bad wire. You are testing with the board unplugged or plugged?
Vanos 1-4.JPG
Do you know how to use WDS? If not I will look but search the numbers on the grounds and you should get a clear path back to the attachment point. I think the ground is the DME, but don't remember.
 

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Discussion Starter #6
Ah I checked the engine side of vanos plug with it un plugged, I will re check connected and report.
No I've not worked WDS but will have a crack at it.
Thanks for this.
 

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Not sure what engine side means so you want to check unplugged and the harness side not the board side. Check on the lowest scale, least sensitive or least accurate. The connector X6460 is in the wire harness on the right side of the engine left of the throttles, long plastic box. Facing forward. It is the same ground used by the oil level sensor, reverse lights and unloader relay. If those other things work then it will be between the vanos and the plug.

What is odd is 2 and 5 go to the same place.
vano ground X6460.JPG

vano ground X6460 location.JPG
 

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Discussion Starter #9 (Edited)
Todays progress.

Ran INPA and DIS, both only show codes 43 and 48, Intake valve vanos advance , cyl 1, and vanos retard cyl 1) No other DME faults (except AA of course)

Testing ohms and continuity on the harness plug Bank 1, the end that disappears under plenum: Pins 2 and 5, the grounds to the vanos solenoids, with the vanos unplugged, ( Changed dmm ground to jump start ground on strut top.)
Reads 14-15 ohms!!! with key on at pin 2 and 5, and 1.8-2 ohms key off. Continuity test on dmm gives the beeping.
Test for voltage: Key on reads .2 -.3 volts!

Did Check of bank 2 , which has no faults, as a reference: Reads 1.0-1.2 ohm key on, and .4 ohm key off, no voltage. Which is what you would expect as normal?
So bank 1 has a problem.
Started at getting into the DME, ( one cover bolt frozen, sprayed it and left to sit o/nite) will attempt to find harness at that end and check continuity back to the vanos plug. and check for problem in DME, not sure where to go there yet, any thoughts appreciated.
Thought easier to start at DME end then remove plenum if DME end checks out, but thinking with voltage on those earths there must be more to it?
 

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You don't need the DME from the connectorX6460 the wire goes by the DME and picks up some other grounds but goes here. Not sure where here is but I am sure you will figure it out. Ground must be broken and you get your ground threw one of the other things on the circuit.
X6452.JPG
 

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Discussion Starter #11
Thanks sailor. i see the spot but RHD must be different, i got brake vac pipe coming out of that moulding, RHD has Dme on left of car, dont see a similar harness on the left side yet, its got to be near the Dme right?
will keep looking,
 

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Discussion Starter #12
Got it, its on left side just below Dme, smaller than i thought.
nothing looks broken, ill undo and clean up the connection.
 

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Discussion Starter #13
No change after cleaning the earth strap from DME to chassis side bulkhead , key on, and same high resistance and small voltage to the earth pin 2 in vanos harness bank 1, and the good bank 2 has normal low resistance and no voltage. continuity test beeps ok bank 1.

Continuity test from pin 2 bank 1 to the earth strap whilst it was undone from the chassis gave continuity ok, and low resistance, key off of course, i disconnected battery to remove the earth strap.

Pushed a clothing pin into the wire about an inch back from the vanos harness plug goes under the plenum, and readings were the same from there too.

Where to from here, plenum off or into Dme.....
 

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Discussion Starter #14
Update

pulled out the bank 1 vanos board again to re test.

Terminal 1 on harness on board which energizes outlet for Inlet cam wont fire with 9v battery, all others work ok. No resistance either, others all 3.9 ohms.

That Noid will only fire from the inner two terminals on little biscuit board, and with a spark every time.

Whats that mean?
 

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Discussion Starter #15
mov out too.

Update

pulled out the bank 1 vanos board again to re test.

Terminal 1 on harness on board which energizes outlet for Inlet cam wont fire with 9v battery, all others work ok. No resistance either, others all 3.9 ohms.

That Noid will only fire from the inner two terminals on little biscuit board, and with a spark every time.

Whats that mean?
And this solenoid's mov is open circiut, other 3 ok.
 

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You will have to get the plenum off. You have a problem on the board but that may have been caused by whatever else is wrong. I would be inclined to disconnect 2 and 5 and run a new ground to them. Then if the car runs fine strip back the harness until you find the fault. It might be one of the other things on that circuit that has failed. You may need to get to connector X6460 and disconnect one thing at a time until you find the fault.
Something is very strange when you get continuity from 2 to the strap when things are disconnected.
 

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Discussion Starter #17 (Edited)
You will have to get the plenum off. You have a problem on the board but that may have been caused by whatever else is wrong. I would be inclined to disconnect 2 and 5 and run a new ground to them. Then if the car runs fine strip back the harness until you find the fault. It might be one of the other things on that circuit that has failed. You may need to get to connector X6460 and disconnect one thing at a time until you find the fault.
Something is very strange when you get continuity from 2 to the strap when things are disconnected.
thanks Sailor

Good thought train yes that looked like my future.

Until this morning i went to check two cyliner ? in the hvac heater water pipes run along inner guard under steer pump reservoir, seem to get quite hot with key on (engine off) whilst doing tests, is that normal? was playing with heat settings seeing if that stopped the heating, when everything shut down, now doors are locked and i cant get in. Hood and trunk open, alarm went off.
All this could be connected?
Did notice when i ran DIS the other day there was a fault mark for hvac and ews , but all was working ok.
Will work out how to open car and keep going. thanks again

Connected charger, says battery is 6.4v !! its only 2y old high quality. Still locked out.
 

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Turns out you have a bigger electrical problem. You should be able to open the doors manually with a brisk turn of the key. The owners manual is in one of the stickys and has good advice to open the car.
 

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Discussion Starter #19 (Edited)
Got into car ok thanks.

Something has floored the battery overnite - took all morning on low charge before it kicked in to higher charge amps.

Not sure if I start again with DIS to find a clue with tracking it, or do the battery drain test pulling fuses one at a time? or just get plenum off and look for harness earth issues first.

Waiting for 12v at battery.

Thanks so much for all your help with this, getting to know a lot about the beast, i have perfected the channel lock pliers( finally located a good pair with almost 90deg head) and screwdriver quick vanos board removal technique now, wish I'd know from the start, no more bashing up wires and scratched noids.

cheeers
 

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Don't use pliers, just get flat head and there is a spot right under the solenoid ! It will help you avoid cracking and breaking MOVs :)
 
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