Technical Well...I'm stumped!

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Technical Well...I'm stumped!

Luke the duke

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Well its official. I am stumped :confused:.

Hello everyone :)

My right side indicators have stopped working altogether (dash light as well).
Left side works fine and both work with hazards. Must be the indicator stalk. confirmed by a little different feel for the right switch. I got one from the wreckers. Changed it out fine. Test it and it works very briefly then nothing.

Damn :bang:.

Fiddling around with it I notice the indicator works when the high beam is engaged.

WTF :eek:.

Considering calling an auto electrician to come and have a look.
Before that I thought to ask you all for suggestions, comments etc.


Few things to consider that might or might not be connected.
1. Back left light had the earth problem. Right one shows no corrosion.
2. Its had a service just before this happened (got it done when I had the windscreen changed for MOT)
3. Little different feel the old indicator stalk had, now feels fine out of the car.


I am at a loss and open to any ideas :)
Luke
 
even with corrosion on back lights you would still get blinker icon on dash
Yes, dash lights work for left and hazards. Its finally gotten to zero today (been minus 11-15 last few days) so I am headed out to change corroded connector today, then checking earths, hazard switch and continuity around switches.
 
Hi all.
Can someone offer some advice on testing the body control unit for my punto.
I've (what seems a common problem) with the indicator only working with the highbeams on. From some previous threads and a little testing of earths, switches etc it seems the body control unit is the culprit. I found one company that says it can repair and another company that would clone to a second hand unit, both cost around 200€.

I would like to do a final test to check the power from the bcu to the column switch to make sure (as best I can) that the problem is the bcu before I send it away. Also I have had the unit out and open and cant see any obvious damage, so I am not 100% sure.
Ive got a wiring diagram and think I know what wires I am looking for, but a little unsure of how to test the connections when they are plugged in and with power.
Does anyone have any advice?
Thanks Luke
 
Hi all.
Can someone offer some advice on testing the body control unit for my punto.
I've (what seems a common problem) with the indicator only working with the highbeams on. From some previous threads and a little testing of earths, switches etc it seems the body control unit is the culprit. I found one company that says it can repair and another company that would clone to a second hand unit, both cost around 200€.

I would like to do a final test to check the power from the bcu to the column switch to make sure (as best I can) that the problem is the bcu before I send it away. Also I have had the unit out and open and cant see any obvious damage, so I am not 100% sure.
Ive got a wiring diagram and think I know what wires I am looking for, but a little unsure of how to test the connections when they are plugged in and with power.
Does anyone have any advice?
Thanks Luke

The lights are turned on by Earthing the various trigger wires from the BCU so if it were the indicator switch at fault, high beam on would result in less Earth potential for the indicator trigger wire which sounds like an unlikely fault because the best earth for the indicator trigger wire would be with high beam off.


You should be able to locate the colour code of the right indicator wire at the BCU and then Earth it and see what happens but it is sort of looking like the fault is inside the BCU and related to high beam having some influence electronically.


I think a BCU from a Finnish wrecker is 130 Euro. You would need to have the EEPROM from your unit swapped over so there goes your 70 Euros to make 200 Euro.

An annoyingly expensive fault which might be simple to fix if you spend a huge number of hours creating a test rig for the BCU or know where the problem lies in advance of opening the BCU.
 
Hi judderbar, and thanks for your thought full response. I have changed the column indicator switch as I thought this seemed the logical problem. The only difference it made was the indicator came on briefly (a few seconds) then went off. I thought it was more likely the result of having the battery disconnected.

Am I right in deducing that if the bcu is at fault there wont be an electrical signal from the bcu to the indicator switch? Is this what you mean by earthing the indicator wire? Not entirely sure how to do this, I cant get to the ends of the connectors without disconnecting them. Do u have any suggestions to do this? It seems I am missing something simple :/

Br
 
Hi judderbar, and thanks for your thought full response. I have changed the column indicator switch as I thought this seemed the logical problem. The only difference it made was the indicator came on briefly (a few seconds) then went off. I thought it was more likely the result of having the battery disconnected.

Am I right in deducing that if the bcu is at fault there wont be an electrical signal from the bcu to the indicator switch? Is this what you mean by earthing the indicator wire? Not entirely sure how to do this, I cant get to the ends of the connectors without disconnecting them. Do u have any suggestions to do this? It seems I am missing something simple :/

Br

you can stick pins into the connector parallel to the wires or just stick a pin thru the wire if you cannot get a pin into the connector.

You still need to eliminate a wiring problem between the BCU and the switch. However if you have the same voltage at the switch for both indicator wires which gets similarly pulled down to Earth voltage by the switch that would suggest the wiring from the switch to the BCU is fine.

I see you might be able to get another BCU very cheaply. If the indicators work you would just need to swap the EEPROM - which is a simple job for an electronics technician. No programming is needed it just needs to be unsoldered from the existing one and put on the other.

https://www.varaosahaku.fi/fi-en/Se...Fuse-box-&-Electricity-central/All/?ps_page=8

My one would cost 70 Euro
 
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you can stick pins into the connector parallel to the wires or just stick a pin thru the wire if you cannot get a pin into the connector.

You still need to eliminate a wiring problem between the BCU and the switch. However if you have the same voltage at the switch for both indicator wires which gets similarly pulled down to Earth voltage by the switch that would suggest the wiring from the switch to the BCU is fine.

I see you might be able to get another BCU very cheaply. If the indicators work you would just need to swap the EEPROM - which is a simple job for an electronics technician. No programming is needed it just needs to be unsoldered from the existing one and put on the other.

https://www.varaosahaku.fi/fi-en/Se...Fuse-box-&-Electricity-central/All/?ps_page=8

My one would cost 70 Euro
Ha :) pins! Of course :)

And great advice I will follow about the voltage test and changing the eprom.
I didnt know any of this, you've taught me alot. Appreciated.

I didnt understand the last line though, are you offering the part, or...?

Either way, first thing is to check the wiring. Then new part and find some one to change the eeprom.
Haha in Finland, not understanding the language that might be the hardest part of all!
Are you Finnish by the way? If not how on earth did you find the part so quickly?!

Thank you very much. I will update here when I know.
Your a champ!
 
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Ha :) pins! Of course :)

And great advice I will follow about the voltage test and changing the eprom.
I didnt know any of this, you've taught me alot. Appreciated.

I didnt understand the last line though, are you offering the part, or...?

Either way, first thing is to check the wiring. Then new part and find some one to change the eeprom.
Haha in Finland, not understanding the language that might be the hardest part of all!
Are you Finnish by the way? If not how on earth did you find the part so quickly?!

Thank you very much. I will update here when I know.
Your a champ!

Sorry about the confusion. I am not selling a BCU.

I am not Finnish but I have been buying parts for my car in Finland for about 7 years.

The Finnish Language is a big problem for me. I thought I would pick it up eventually but it is not happening so far.

Another option for you is to buy the full set of locks, ECU and BCU from Ebay UK. Prices were around 100 pounds.
 
Well. I went to test the wiring today. The haynes wiring diagram shows purple/white and purple/black colour from the bcu. There are no purple wires from bsu to stalk! There are actually no purple wires period, from bsu or fusebox. Any ideas??
 
Sorry about the confusion. I am not selling a BCU.

I am not Finnish but I have been buying parts for my car in Finland for about 7 years.

The Finnish Language is a big problem for me. I thought I would pick it up eventually but it is not happening so far.

Another option for you is to buy the full set of locks, ECU and BCU from Ebay UK. Prices were around 100 pounds.
I've been in Finland about the same amount of time and my Finnish is non existent. Luckily most people in the south speak english enough to get by. Bloody hard to find anything on the internet still and trying to explain what I need to my wife is like pulling teeth. :) lovely day today though. Pity about the car :(
 
I've been in Finland about the same amount of time and my Finnish is non existent. Luckily most people in the south speak english enough to get by. Bloody hard to find anything on the internet still and trying to explain what I need to my wife is like pulling teeth. :) lovely day today though. Pity about the car :(

Well the lovely weather continues and I am supposing you can drive around on high beam without it causing too many problems? :) Does the indicator still work with high beam fuse removed? - I am supposing there is a separate relay for high and low beam. Relays are marked on the engine fuse box cover. Haynes says high beam is relay 1.


I will see what my indicator wiring looks like and see how easy it is to test and report back.
 
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I have had similar problems.Sometimes the car will not start, when that happens i have no central locking,windows, fuel gauge .I have had the BCM out.Cleaned all the earths etc.Is there anything else i can check
 
I have had similar problems.Sometimes the car will not start, when that happens i have no central locking,windows, fuel gauge .I have had the BCM out.Cleaned all the earths etc.Is there anything else i can check

You can buy a second hand BCM for a 1999 car very cheaply. If you fit that and dont get all of the other electrical problems you can try to swap over the eeprom so the car will start.
 
Luke. did you sort your problem out?, i found a new BCM on Ebay for a tenner and my problems are sorted i just need to swap the EEPROM over to make it start, if i can find someone in my area to do it
 
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