Electric step problems

[Derek Uzzell]

kevandali - 2011-12-06 5:31 PM

 

...Derek... I think that the leisure batteries may have not been charging for some time but hard to know as the van has been on elecric hook up for most of year and not really used on leisure batteries only but assume they must be getting charged somehow or they would be flat as a pancake, unless they have been trickle charged from the mains? Kev

 

As your motorhome has been continuously on EHU, it seems reasonable to assume that the on-board battery-charger has also been operating continuously during that period. If that's the case, then the normal expectation would be for the charger to be continuously charging your leisure batteries (after all, that's the battery-charger's primary purpose), which would, of course, explain why they are not flat.

 

I don't know if your Suntor's electrical system also allows charging of the vehicle battery using the on-board charger, but there's nothing in the AC85 description

 

http://www.sargentltd.co.uk/AC85_Control_Panel.pdf

 

to suggest this is possible.

 

The AC85 seems to be a straightforward 'caravan-style' control-panel with a 3-way Leisure-battery/OFF/Vehicle-battery power-selection switch that allows 12V power for the motorhome's habitation equipment (lights, water-pump, etc.) to be drawn from either the leisure batteries or the vehicle battery.

[Keithl]

Hi Kev and all,

 

My apologies for not joining in the discussion today but I've been on a training course with no access to internet.

You're going to love this, the course was on "Hazardous Voltages in Hybrid Vehicles" :D

All I can say is think yourselves lucky that no-one is building Hybrid MH's (yet).

 

Right back to matters in hand...

 

Kev, I still believe your problem lies in these 3 fuses and/or the relays feeding them! The reasons being that your readings at these fuses have changed during your testing from one being permanently lived to now 2 and the middle fuse only having voltage at one end to now both.

All your other readings with EHU on and off back up this theory.

 

In a much earlier post you said your auto electrician had repaired or replaced your 'charging fuses', please can you elaborate further why and exactly what he did as he must have suspected a fault in the same place we are suggesting.

 

Keith.

[Keithl]

Derek Uzzell - 2011-12-06 6:59 PM

I don't know if your Suntor's electrical system also allows charging of the vehicle battery using the on-board charger, but there's nothing in the AC85 description

 

http://www.sargentltd.co.uk/AC85_Control_Panel.pdf

 

to suggest this is possible.

 

The AC85 seems to be a straightforward 'caravan-style' control-panel with a 3-way Leisure-battery/OFF/Vehicle-battery power-selection switch that allows 12V power for the motorhome's habitation equipment (lights, water-pump, etc.) to be drawn from either the leisure batteries or the vehicle battery.

 

Derek,

 

When the selector switch is in the Vehicle battery position then the charger will charge the vehicle battery and the hab electrics run off it as well. ie the Hab battery will be out of the circuit.

 

Keith.

[Robinhood]

The last Swift 'van I had (and it was some time ago), charged whichever battery was selected on the panel with the onboard charger.

 

I know it worked, 'cos I managed to get enough juice into a dead starter battery once in Scotland to get the van started (and then drove to Fort William to get it replaced - the battery, that is).

 

The facility to do this on Kev's van would explain why the step works on hook-up with the switch to vehicle battery (though of course, this could just be another anomaly ;-) )

[Keithl]

Robinhood - 2011-12-06 7:07 PM

The facility to do this on Kev's van would explain why the step works on hook-up with the switch to vehicle battery (though of course, this could just be another anomaly ;-) )

 

No not an anomaly, but just proves that the step is functioning correctly and the fault lies in the power feed from the lower fuse.

[kevandali]

In the morning I am going to do the test that Brambles described but also carry out all my other tests again to see if I get the same result, I think that being able to see properly and not battling with the weather helped me test things out more accurately.

 

Had an email and I think Derek also suggested that as a temp measure I could always run a lead from the leasure battery complete with a 20 amp fuse, to the step switch permenant live connection and that should get the step working?

 

As for the leisure batteries not charging from the alternator, not sure about that one yet?

 

Just a thought, could I do a continuity test from the third fuse to the connection at the back of the step switch, which would tell me if there was a break in the cable?

 

 

 

[Robinhood]

Keithl - 2011-12-06 7:16 PM

 

Robinhood - 2011-12-06 7:07 PM

The facility to do this on Kev's van would explain why the step works on hook-up with the switch to vehicle battery (though of course, this could just be another anomaly ;-) )

 

No not an anomaly, but just proves that the step is functioning correctly and the fault lies in the power feed from the lower fuse.

 

It was tongue-in-cheek, Keith. It is doing exactly what I would expect.

 

The checks that Brambles has suggested above would be a good next step, as it takes us back to the basics of the power supply (and hasn't, so far as I know, been tried yet without the fuses in).

[Keithl]

as a temp measure I could always run a lead from the leisure battery complete with a 20 amp fuse, to the step switch permenant live connection and that should get the step working?

 

Yes, but disconnect the existing Brown/Green wire from the switch to prevent any unexpected happenings.

 

Just a thought, could I do a continuity test from the third fuse to the connection at the back of the step switch, which would tell me if there was a break in the cable?

 

Yes, the result will be interesting. It should be the Brown/Green wire disconnected above.

 

Keith.

[Keithl]

Keithl - 2011-12-06 7:02 PM

In a much earlier post you said your auto electrician had repaired or replaced your 'charging fuses', please can you elaborate further why and exactly what he did as he must have suspected a fault in the same place we are suggesting.

 

Keith.

 

Kev,

 

Do you know what the auto electrician did please?

 

Keith.

[Keithl]

Keithl - 2011-12-05 1:42 PM

I have another suggestion to check...

 

First measure the voltage at both sides of the (bottom) fuse and then if the same, whilst you measure the voltage at the fuse get a helper to press the switch to extend the step and see what happens to the reading. It may help to isolate the problem.

 

Kev,

 

Sorry to keep bombarding you with questions but did you try this simple test, if not please could you.

 

Thanks,

Keith.

 

Edit, With engine off and Mains off.

[Brambles]

I have just read the posts again re tests done. heck it is comfusiing and realise you have actually given me the results I need. but later they contradict.

So one more thing to check as well. Have you actually checked the fuses with your meter rather than just look at them. Take them out and using ohms/resistance on your meter check they really are actually OK still.

Jon.

 

 

[Robinhood]

He's done that, Jon.

kevandali - 2011-12-05 3:23 PMSo much info, all good. (stopped snowing in notts now)

I have checked the continuity of all 3 fuses by having the meter on ohms and the audible sound on, all three bleeped happily.

I'm concerned that all the results don't seem consistent, but the latest tests at the fuseholder look (if I can get my mind round it) correct - but they may not be completely.

[Robinhood]

Kev,

 

If you haven't been too careful at each point as to which battery was being selected by the panel, I think I can make sense of (some or all of) your varying results.

 

Personally, I think that not knowing this position for each set of results is causing some considerable confusion, and I'm not at all convinced that the problems are as great as they may seem.

 

At the moment, from a combination of your latest results, and conjecture about switch position on previous testing, the step at least may simply be a broken wire between the bottom fuseholder and the switch feed.

 

Looking at your latest results:

 

With switch in engine position and engine running have voltage to both sides of all 3 fuses

 

entirely normal - fed by alternator via relays (top and middle 2) and vehicle battery direct (bottom 1)

 

With engine off, no voltage to top fuse

 

entirely normal - top isolated by relay, middle isolated by relay but fed by leisure battery, bottom fed by vehicle battery direct.

 

With everything off and switch in engine or leisure position, no power to any connections behind the step switch.

 

not normal - and switch position should have no effect in this case, as step should be fed by permanent feed from vehicle battery regardless

 

With mains on and switch in leisure position, no voltage to any connection behind step switch

 

entirely normal - leisure battery circuit does not feed step switch

 

With mains on and switch in engine battery position, have voltage on the permanent live connection behind step switch

 

entirely normal - step switch that should normally rely on permanent vehicle battery feed is now drawing power from onboard power supply

 

With mains on and switch in leisure position, ameter needle on control panel swings into green

 

entirely normal - measuring onboard charger voltage to leisure battery circuit

 

With mains on and switch in engine battery position, ameter needle on control panel swings into green

 

entirely normal - measuring onboard charger voltage to vehicle battery circuit

 

When mains off, and switch in leisure position, ameter reading for leisure battery is into green and main habitation lights work fine

 

entirely normal - 12v systems working off leisure battery circuit

 

When mains off, and switch in engine battery position ameter reading for engine battery does not move and habitation lights do not work

 

not normal - 12v systems should work with vehicle battery in circuit

 

With engine off and mains off, leisure batteries 12.9v each engine battery 12.6v

 

reasonable values

 

With engine running, engine battery 14v+ leisure batteries no change

 

Slightly odd- Engine battery OK but would expect something at leisure batteries

 

With mains on, all batteries appear to stay the same?

 

Again, slightly odd - if there is as suspected a broken connection I would not expect to see any change at the vehicle battery, but would possibly expect to do so at the leisure battery. Did you have the switch in the appropriate position for each battery type when testing?

 

The maxi fuse and the fuse protecting the leisure batteries are ok

 

good

 

 

I'm going to separate the two problems

 

First the step.

 

If we assume that your readings are correct, two simple tests will zero in on the broken wire theory, which, at least as far as the step is concerned is still entirely consistent with your results:

 

Mains off, switch to leisure battery.

Bottom fuse out

Test the output side of the fuse holder (RH end in the diagram)

 

If this shows no volts (I hope it does) -

 

Mains on, switch to vehicle battery

Bottom fuse still out

Test the same output side of the fuse holder

 

If this still shows no volts, I believe you have a discontinuity between the RH end of the fuseholder, and a joint where it should split to the panel and the step switch.

 

Second, leisure battery charging:

 

I'm confused with this, as I'm not entirely convinced about the measurements (or even if there is a problem), but taking them as correct, and given its proximity, I'd suggest a test of the EMC relay.

 

So,

 

Mains off, Panel switch to Leisure, habitation light(s) on

Start engine

Do lights go off?

 

 

I really don't think the answer is far away.

 

[kevandali]

Braving the cold and dark morning and taking the dogs out, then will carry out all the above tests and any more I can think of and report back. Really do appreciate all the help :-)

[Derek Uzzell]

Keithl - 2011-12-06 7:04 PM

 

Derek Uzzell - 2011-12-06 6:59 PM

I don't know if your Suntor's electrical system also allows charging of the vehicle battery using the on-board charger, but there's nothing in the AC85 description

 

http://www.sargentltd.co.uk/AC85_Control_Panel.pdf

 

to suggest this is possible.

 

The AC85 seems to be a straightforward 'caravan-style' control-panel with a 3-way Leisure-battery/OFF/Vehicle-battery power-selection switch that allows 12V power for the motorhome's habitation equipment (lights, water-pump, etc.) to be drawn from either the leisure batteries or the vehicle battery.

 

Derek,

 

When the selector switch is in the Vehicle battery position then the charger will charge the vehicle battery and the hab electrics run off it as well. ie the Hab battery will be out of the circuit.

 

Keith.

 

OK, I've re-read the MotorhomeFacts thread and noted Ian Sargent's advice regarding Swift motorhomes fitted with an analogue control-panel:

 

"QUESTION - Mine is a 2005 Swift Suntor (Sundance) with an analogue volt meter and a three position switch to choose which battery to use when off mains supply. I understood that the mains charger would charge the leisure battery when in the middle (off) position and the leisure battery position. Is that right? And presumably it will charge the vehicle battery when in that position?

 

ANSWER from Ian Sargent - ...on your vehicle the charger will provide the van power when in the centre position, but with the charger on and if you select the vehicle battery this will be charged, similarly if the leisure battery is selected this will be charged."

 

It's probablly not significant, but the needle-type test-gauge on an AC85 control-panel indicates battery-voltage not amps and (I presume) can provide a read-out of whichever battery has been selected via the 3-position switch.

[Brambles]

I would concentrate on the outputs connection of the third fuse ( Engine battery volts) and make sure the crimped connections for spades is ok. Also the wire from the middle fuse ( leisure battery Volts).

The fault definetly lies in this area or with those cables from the putoput of the fuses.

 

Agree with Robin, the solution is very close. I do not think the EMC relay is a problem though.

[kevandali]

Ok, just got back inside to warm up, carried out the same tests again plus ran a cable from the permanent live cable at the back of the step switch back towards the third fuse, tested continuity between the cable and the output of the fuse with fuse removed and got nothing.

• With switch in engine position and engine running have voltage to both sides of all 3 fuses Not correct, with fuses out, top fuse 0v and 14.3v, middle fuse, 10v and 14.3v, bottom fuse 14.3v and 0v, with fuses in got voltage from both sides of all fuses.

• With engine off, no voltage to top fuse Correct

• With everything off and switch in engine or leisure position, no power to any connections behind the step switch.Correct
• With mains on and switch in leisure position, no voltage to any connection behind step switch Correct

• With mains on and switch in engine battery position, have voltage on the permanent live connection behind step switch Correct but 10.9v

• With mains on and switch in leisure position, ameter needle on control panel swings into green Correct
• With mains on and switch in engine battery position, ameter needle on control panel swings into green Correct
• When mains off, and switch in leisure position, ameter reading for leisure battery is into green and main habitation lights work fine Correct
• When mains off, and switch in engine battery position ameter reading for engine battery does not move and habitation lights do not work Correct
• With engine off and mains off, leisure batteries 12.9v each engine battery 12.6v Correct reading were a little higher

• With engine running, engine battery 14v+ leisure batteries no change Correct, tested a few times but no rise in voltage at the leisure batteries.

• With mains on, all batteries appear to stay the same? Incorrect, the leisure batteries definitely increased in voltage, tried moving selector switch to the engine battery position on the control panel but the voltage at the engine battery did not increase.

• The maxi fuse and the fuse protecting the leisure batteries are ok  Correct

Just going to ask a neighbour to press the step switch while I monitor the voltage at the fuse, will edit in 10 mins.

 

[Brambles]

Arrrrrgh! you are still not confirming the information required, almost but not quite.

 

•With switch in engine position and engine running have voltage to both sides of all 3 fuses Not correct, with fuses out, top fuse 0v and 14.3v, middle fuse, 10v and 14.3v, bottom fuse 14.3v and 0v, with fuses in got voltage from both sides of all fuses.

 

In this test you said you got voltage both sides of all fuses. I do not want to make any assumptions here. What are the actual voltage readings with fuses in? It may sound pedantic but is important to eliminate any doubt.

[kevandali]

Brambles - 2011-12-07 10:26 AMArrrrrgh! you are stil not comformning teh information requires, almost but not quite.•With switch in engine position and engine running have voltage to both sides of all 3 fuses Not correct, with fuses out, top fuse 0v and 14.3v, middle fuse, 10v and 14.3v, bottom fuse 14.3v and 0v, with fuses in got voltage from both sides of all fuses.In this test you said you got voltage both sides of all fuses. I do not want to make any assumptions here. What are the actual voltage readings? It may sound pedantic but is important to eliminate any doubt.

 

The readings were all just over 14v from both sides of fuses 2 and 3 and 13.6v from both sides of fuse 1.

 

[Brambles]

OK.

You now need to concentrate on fuse 2 and the 10 volts you had when the fuse was removed.

This should be the leisure battery voltage so you need to physically and/or electrically trace this from the fuse back to the 20 amp fuse for the leisure battery.

 

So yu could start by measuring the voltage at the 20 amp battrey fuse. Check it is 12 volts. Now somewhere along this connection/cable/terminals it is going to change from 12.8 approx volts to 10 volts. Hopefully this will enable you to find the break in this connection.

[Robinhood]

Just got back from visiting Kev. (I got an hour's delay on the required taxi-run, Kev, hence the posting ;-) )

 

Whatever state it has been in in the interim tests, the alternator IS now charging the leisure batteries.

 

The fuseholder and fuses are fine, but there is a definite discontinuity in the Brown/Green wire (permanent live) from the bottom fuse.

 

The permanent live joint teed from this to the step switch is not anywhere in sight (it does not, as the diagram implies, split at the fuseholder, or anywhere else visible under the bonnet).

 

We can see the main brown/green wire at the panel end, and the step switch permanent live is a thinner gauge brown/green. Kev is going to try to track this back to the joint with the thicker battery-connected brown/green. A bit of furniture dismantling may be required.

 

He needs to check the joint, and if that is OK, there is a break somewhere between that and the fuseholder. Since the splitter on the fridge fuse leg that drives the automatic step retraction is a plug, with a single feed one end, and a double wire at the other end - I would think there is a plug lurking somewhere, which may have backed-off or corroded. If not, it will be a wire break.

 

 

[kevandali]

Robin Hood/Bob came to the rescue, now realise that the problem is a break in the brown/green cable somewhere between the fuse and before the joint that splits to the step switch. Found out that all the cables actually run under the floor underneath the van. Found a big joining connector box behind the pan drawer at the bottom of the oven but all it does is actually break the brown/green wire, tested continuity between the plug and the wire at the back of the step switch and had continuity. Cannot see any other joining connection boxes underneath the van and have traced it all the way back to the fuse. Its all taped up so not sure where the break could be as it all looks fine.

Will try and take a better look soon.

 

As for the charging of the batteries, all is fine, leisure batteries charge on mains and alternator, engine battery charges on alternator but not on mains due to the possible break in the cable, I can live with the vehicle battery not charging on mains as I never used that anyway, but going to try and find the break if possible.

 

Also checked if there was power on the brown/green connection at other side of the connection plug and no power found.

 

Maybe will have to solve the problem by simply running in a new live feed (fused) to the step switch and make do with the vehicle battery not charging on mains?

 

[Brambles]

Oh well done chaps. This break though, remember there was 9.6 volts at rear of step switch so goes somewhere. 9.6v is very close toe the 10 measured on fuses when fuses where pulled. Is there a clue there. Have you also checked behind the control panel with the switches and meter. It may be joined behind there or connected to the wrong place.

[Robinhood]

kevandali - 2011-12-07 3:29 PM

Maybe will have to solve the problem by simply running in a new live feed (fused) to the step switch and make do with the vehicle battery not charging on mains?

 

Kev,

 

I'm trying to make sure I understand what You're saying. Is the following correct?

 

===

 

You've been into the back of the pan drawer as suggested and found a multi-plug (in which the thick brown/green wire features).

 

You've tested from the brown/green to the rear end of this plug to the switch step permanent feed and got continuity. (implying the tee to the switch is somewhere to the rear).

 

You've tested for power on the brown/green down the other, forward, part of the plug, and got none (implying the break is still forward of this).

 

===

 

If this is the case, I'd suggest you bite the bullet and complete the test.

 

Run your long piece of spare wire wire from the bottom fuseholder output, to the brown/green wire on the rear side of the plug you've just found. By doing this you should have bypassed the break and completed the original circuit.

 

Test your step, and test the vehicle battery voltage at the panel.

 

If these now both work (as I hope they should - you shouldn't need to test that the vehicle battery charges from the onboard charger) I'd suggest you do the job properly, and route a wire internally to do this. From what I've seen, it shouldn't be too difficult, (follow the existing out of the engine bay, and route under the flooring and plastic footwell tray?) and you will get full original function back.

 

If the test above worked OK, you should be OK snipping the green/brown wire from the front half of the plug mentioned above, and bullet-connecting (easier than trying to replace/re-insert a wire into the plug). Make sure you use at least the same grade (thickness) of wire as is already there.

 

 

Good Luck

 

[Robinhood]

Brambles - 2011-12-07 4:24 PM

 

Oh well done chaps. This break though, remember there was 9.6 volts at rear of step switch so goes somewhere. 9.6v is very close toe the 10 measured on fuses when fuses where pulled. Is there a clue there. Have you also checked behind the control panel with the switches and meter. It may be joined behind there or connected to the wrong place.

 

Jon,

 

I'm not sure all the voltages were reliable, and I only had enough time to do basic diagnosis.

 

I did get chance to see what the layout was like though.

 

What Kev has found is still consistent with a break forward of the tee. This is also consistent with his problems.

 

The final test I've suggested will (I believe) provide "proof of concept", if not actually show where any possible break is.

 

If it works, it will, IMO, be safe to bypass the suspect wire as I have suggested.