CAN Bus & Electronics - a nightmare story for you.
Discussion
Prompted by this https://www.pistonheads.com/gassing/topic.asp?h=0&...
What is it with vehicle technology that leads to a situation like this?
Reliability and user serviceability of modern day car electronics (bulbs in this case) makes it impossible to actually fix problems.
Especially French wiring looms and super 'intelligent' CAN buses monitoring everything.
It has been dumbed up to such a high level now that you haven't got a chance mate.
A mate of mine had a headlight bulb blow in his Ford Transit Connect van. The rear tail light failed at the same time.
We replaced all the bulbs and just could not get it working. WTAF? - dash display claimed short detected in near side lighting circuit.
A few hours poking around and I gave up.
He had to take it to a Ford technician (fortunately not a main dealer but a lad we know) to get the BCM reset and it all started working again.
The only conclusion is that when the filament broke a short was detected by the BCM and it shut down that circuit and would not turn it back on again with out guidance from a laptop wielding Ford knowledgeable tech.
It's utter nuts. £x amount trying bulb after bulb, inspecting wiring, testing bulbs, dicking about, making calls, how much time?
Eventually F-Tech lad wanted £50 for the time sorting this, then you add on the cost of fuel to get to him, the number of hours spent looking at it your self and then the number of hours that van was not working.
It's a disgrace.
^ Correct. - Sorry BCM is Body Control Module - it monitors all the lights (and likely anything anything else like boot opening control or a mechanised soft top roof).
It's an impossible situation.
(Long story)
On another post I related a story about a SEAT (of some version or other) where the ECU had given up. The car had been sat with a main dealer for weeks with no resolution so eventually it was trailered back to my mates yard.
It belonged to a family member of my friend who runs the yard (we generally work on plant kit not cars), the vehicle was sat on the yard for months before we found someone (a VW specialist???) that knew what was likely wrong & would take look at it.
Turns out there was/is a common fault on these vehicles where the water temp sensor leaks and after time the coolant creeps up via capillary action along the wires and in to the ECU connector and corrodes it beyond belief.
So this lad turns up, spends a few hours changing over the plug and starts it on the first turn of the key - I couldn't believe it.
Then he whips out his Snap-On super dooper ODBII device and with in a few minutes he's cleared all the error codes and they vehicle is perfectly happy and ready to go.
I asked him how much did that Snap-On device cost you? 'It's a couple of grand mate but I just bring it home from work for the weekend'.
'And the updates for the software, how much is that?'
'About 900 a year mate'.
Holy f
k, no wonder these lads are out on the road at the weekend using borrowed dealer level kit and earning a few extra quid.
No home mechanic can compete with that when it comes to trivial matters like a bulb has blown.
TLDR; make friends with a Polish lad, or a main dealer tech who does work on the side & has the kit to look into these electrical problems. The days of fixing these issues with a multimeter and a bit of common sense are long gone.
It's an impossible situation.
(Long story)
On another post I related a story about a SEAT (of some version or other) where the ECU had given up. The car had been sat with a main dealer for weeks with no resolution so eventually it was trailered back to my mates yard.
It belonged to a family member of my friend who runs the yard (we generally work on plant kit not cars), the vehicle was sat on the yard for months before we found someone (a VW specialist???) that knew what was likely wrong & would take look at it.
Turns out there was/is a common fault on these vehicles where the water temp sensor leaks and after time the coolant creeps up via capillary action along the wires and in to the ECU connector and corrodes it beyond belief.
So this lad turns up, spends a few hours changing over the plug and starts it on the first turn of the key - I couldn't believe it.
Then he whips out his Snap-On super dooper ODBII device and with in a few minutes he's cleared all the error codes and they vehicle is perfectly happy and ready to go.
I asked him how much did that Snap-On device cost you? 'It's a couple of grand mate but I just bring it home from work for the weekend'.
'And the updates for the software, how much is that?'
'About 900 a year mate'.
Holy f
k, no wonder these lads are out on the road at the weekend using borrowed dealer level kit and earning a few extra quid.No home mechanic can compete with that when it comes to trivial matters like a bulb has blown.
TLDR; make friends with a Polish lad, or a main dealer tech who does work on the side & has the kit to look into these electrical problems. The days of fixing these issues with a multimeter and a bit of common sense are long gone.
Penelope Stopit said:
While on the subject of water
Some may appreciate this Canems installation, apparently carried out by a professional, image shows the main relay and ECU
Floor of car is below ECU
You couldn't make this up yet it happened
Don't even get me started on the genius designer at renault who thought it would be smart cool and clever to mount the Clio's air bag ecm directly underneath the coffee cup holder Some may appreciate this Canems installation, apparently carried out by a professional, image shows the main relay and ECU
Floor of car is below ECU
You couldn't make this up yet it happened
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