Still seeking help with starting issue.

[gyislander]

I posted back in April about a wierd starting issue but unfortunately got no replies and the issue is still ongoing and driving me nuts !

I have a 2011 Ford Ka 1.3 tdci. The car starts first turn of the key but the battery light stays on and the electric power steering doesnt click into action. There are no steering fault lights and no EML. If I switch off and restart ... but only within 20 seconds ... the battery light goes out and the steering works fine. Even if I just cycle the ignition on/off then start the car runs without any issues. Even when the battery light is on the car is charging at 14v. The battery is brand new and I tried another steering unit in the car but no difference.

I've generally good mechanical knowledge/experience but modern electronics remain a mystery. I've googled everything I can think of, bought books on vehicle electronics, found the 4cardata site a fantastic educational resource but I'm still stumped !

My scanner won't recognise the car as a Ka but will as a Fiat 500 ( I believe they're pretty much identical ). I have no fault codes other than an occasional "inertia function intermittent" but that doesn't bring on the EML. I have obtained the Fiat wiring diagrams (4cardata) and run continuity tests on the alternator wiring and the CAN system. I have switched relays around, checked every fuse and tested voltage on everything I can think of but found no differences in anything when running/starting faulty or perfectly. I have also removed and cleaned every earth I can find . I did notice that voltage on the CAN starts at 12v then switches to about 4.6v when running. Switch off and it climbs again to 12v in around about the critical 20 seconds but perhaps thats just coincidence.

Only other oddity I found was that the owners handbook says to depress the clutch on starting the car, not sure if thats given as advice or a neccessity as the car does have a position switch (tested and wired correctly to the BCM and ECU) but starts whether depressed or not.

I know that one of the ignition wires to the BCM is to "wake up" the system which I thought might be the issue but again I can't find any problems in that supply. I now understand that the alternator signals its output to the ECU which inputs that and signals from the RPM sensor to the BCM and CAN which triggers the battery light if its not happy. I can't figure out if the steering doesnt come on because the BCM thinks the car is short on volts or if the battery light is on because (for whatever reason) the steering isnt functioning.

Any expertise would be greatly appreciated as I live on an island where professional options are very limited !

 

[Pete999]

Daft question, but have you tried a auto electrical or a Ford vehicle Forum?

 

[telectrix]

i's same as OP. fix anything with a hammer, spanner, baling wire, and Mole Grips, but when it comes to vehicle electronics, I'm buggered.

 

[snowhead]

I would agree that the ECU is not enabling the Steering due to low Voltage, it will also hold off the A/C and any other power heavy items.
I would also suspect either a bad earth or poor connection / high resistance connection.
Possibly the alternator as well.

 

[gyislander]

Daft question, but have you tried a auto electrical or a Ford vehicle Forum?

Tried a couple of Ford forums but got nothing really. As I said I'm on an island currently with severe travel restrictions so an auto electrician isn't really an option. That said its probably a last resort, I always enjoy fixing a challenge myself often with the invaluable help of an expert forum.
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If it is down to a bad connection I just can't figure out why the simple on/off ignition is all it takes to start/run perfectly ? What is that extra on/off doing that makes all the difference ?

 

[static zap]

Electric steering does take a good whack out of the battery , so makes sense it waits for it to "think" the engine is
running before turning it on.
(May need to safely hook up a cheap multimeter to
aux power socket (if you have one!) .
Check if it always charges .
May be an ECU decision for energy saving !
(Light may also be ECU controlled
-rather than traditional bulb feeds alternator-
(if have any detail of alternator wiring ? )
(Monitored a lazy alternator on an old Banger)

 

[telectrix]

Tried a couple of Ford forums but got nothing really. As I said I'm on an island currently with severe travel restrictions so an auto electrician isn't really an option. That said its probably a last resort, I always enjoy fixing a challenge myself often with the invaluable help of an expert forum.
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If it is down to a bad connection I just can't figure out why the simple on/off ignition is all it takes to start/run perfectly ? What is that extra on/off doing that makes all the difference ?

car electrionics = witchcraft.

 

[static zap]

car electrionics = witchcraft.

Nah I blame the shake , rattle n roll .
( Are you plagued by speed bumps in town or just pot holes ! ?)

 

[telectrix]

not that many speed humps round here, and they fill in the potholes within 6 months of marking them. horses need re-shoeing evey 6 weeks and the carriage wheel repair guy is exceedingly busy.

 

[ruston]

So do you depress the clutch while cranking? If so does is make any difference . I don't suppose this car has stop start?
Canbus signals are 2.5 volts low and 5 volts high so your voltage could be normal depending on the conditions.

 

[gyislander]

It makes no difference if I depress the clutch. The reason I went through all the hassle to get the switch out and test is was because I noticed that in live data and running in either scenario there was no change to depressing it or not. Doesn't have stop start. I once tried reading the car as a Fiat Panda diesel and there in live data on engine status it has readings of "parking" "starting" and "running". In the faulty scenario it never changed from parking but on 2nd start/ignition cycle it changed through the 3. I took that to mean that when its faulty its because the car doesn't realise it been started though with a Panda obviously not being a Ka or even 500 I'm not sure if I should put any weight on that finding,
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Electric steering does take a good whack out of the battery , so makes sense it waits for it to "think" the engine is
running before turning it on.
(May need to safely hook up a cheap multimeter to
aux power socket (if you have one!) .
Check if it always charges .
May be an ECU decision for energy saving !
(Light may also be ECU controlled
-rather than traditional bulb feeds alternator-
(if have any detail of alternator wiring ? )
(Monitored a lazy alternator on an old Banger)

Not sure what you mean or why hook up to socket ? Does always charge properly, bulb is on the CAN system rather than directly wired.

 

[ruston]

Have you had any problems in the past with the key fob or immobilizer.
Immobilizers can be a source of problems.

 

[gyislander]

No immobiliser issues. I bought the car for the Mrs as a spares/repairs due to some light panel damage. When I drove it first the battery light was on and the power steering didn't work which I thought was probably just the belt (didn't realise it was electric) . I grabbed a new battery and belt incase it failed on the drive home but it didn't. When I stopped I tried a restart to make sure it would be ok (to board ferry) and was suprised to find an easy start with no light and with working steering.
I must have started the car hundreds of times in the last few months and its always the same.
Car hasn't been on the road since as I try to get to the bottom of the issue.

 

[ruston]

How light was the damage , any chance any parts of the harness have been penetrated ( especially around the alternator ) or crushed, or any plugs damaged.
Was the body damage the only reason it was spares or repair, or did they not give you any information?

 

[gyislander]

The damage was very light, mainly scrapes and scratches, a cracked screen and a bogging interior ! Interestingly the alternator looks like the cleanest/newest part of the car. I've just checked again and the voltages from the alternator main lead and ecu wire are consistent in either running scenario. Voltages to main steering supply and ignition based supply also remain similar.