peugeot alternator problems
Discussion
Hi Guys need some experienced brains to help me with a problem.
I have a Peugeot 208 1.2 5 Door hatchback 2015.
I have been having a charging issue with the car and first thought was battery. I took the battery for testing and was told it was in good working order.
I then purchased a re-manufactured alternator to be fitted by local mechanic. This did not solve the problem and he said it was because it wasn't an original equipment alternator. So i went to dealers and bought another alternator at three times the price, this also didn't solve my problem. When the plug is removed from the back of the alternator it will send 14.01 amps to the battery, when I plug it back in this drops to 12 volts and below.
Is this a common fault? Does anyone know what is causing this variation?
I have a Peugeot 208 1.2 5 Door hatchback 2015.
I have been having a charging issue with the car and first thought was battery. I took the battery for testing and was told it was in good working order.
I then purchased a re-manufactured alternator to be fitted by local mechanic. This did not solve the problem and he said it was because it wasn't an original equipment alternator. So i went to dealers and bought another alternator at three times the price, this also didn't solve my problem. When the plug is removed from the back of the alternator it will send 14.01 amps to the battery, when I plug it back in this drops to 12 volts and below.
Is this a common fault? Does anyone know what is causing this variation?
Thanks for the prompt replies guys
The original problem was the battery kept going flat so i presumed the battery was goosed. Had that tested and told all good.
The mechanic said to take it autoelectrician who wants £100+ to diagnose so thought i would try get advice first from here.
The reading is from the battery with the engine running.
The original problem was the battery kept going flat so i presumed the battery was goosed. Had that tested and told all good.
The mechanic said to take it autoelectrician who wants £100+ to diagnose so thought i would try get advice first from here.
The reading is from the battery with the engine running.
Do the following readings
Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Alternator output & negative engine off (should read 12V)
Alternator output & negative engine on (should read ~14.4V)
On the alternator, there will sometimes be 2 cables, 1 is thick, goes back to the battery, the other is an 'excite' wire, that tells it to output voltage. The 'plug' I'm assuming is the one that runs back to the battery, is there a metal surface on it you can test voltage with?
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Alternator output & negative engine off (should read 12V)
Alternator output & negative engine on (should read ~14.4V)
On the alternator, there will sometimes be 2 cables, 1 is thick, goes back to the battery, the other is an 'excite' wire, that tells it to output voltage. The 'plug' I'm assuming is the one that runs back to the battery, is there a metal surface on it you can test voltage with?
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
illmonkey said:
Do the following readings
Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
Sorry, not correct ~12v means the battery is basically flat.Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
A 12 volt battery is actually 6 x 2.1 volt cells in series so a fully charged battery should be 12.6 volts, ands every 0.1 volt down from that means that it has lost around 20% of its charge.
Measure as above but you should get 12.6 volts and to ensure it is fully charged you should put it on a battery charger for at least 12 hours, then test it 30 min after removing from charge, then start the engine & see what you are getting across the battery.
illmonkey said:
Do the following readings
Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Alternator output & negative engine off (should read 12V)
Alternator output & negative engine on (should read ~14.4V)
On the alternator, there will sometimes be 2 cables, 1 is thick, goes back to the battery, the other is an 'excite' wire, that tells it to output voltage. The 'plug' I'm assuming is the one that runs back to the battery, is there a metal surface on it you can test voltage with?
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
It's a smart charge alternator, things have moved on.Live & negative engine off (should read ~12V)
Live & negative engine on (should read ~14.4V)
Alternator output & negative engine off (should read 12V)
Alternator output & negative engine on (should read ~14.4V)
On the alternator, there will sometimes be 2 cables, 1 is thick, goes back to the battery, the other is an 'excite' wire, that tells it to output voltage. The 'plug' I'm assuming is the one that runs back to the battery, is there a metal surface on it you can test voltage with?
Even the most basic garage could do a battery and/or alternator test, I suggest going somewhere else.
From what the OP says if he's getting 14v with the smart charge disabled then the alternator is probably working and the problem lies elsewhere. It will need a 'scope to test it properly.
M_A_S said:
It's a smart charge alternator, things have moved on.
From what the OP says if he's getting 14v with the smart charge disabled then the alternator is probably working and the problem lies elsewhere. It will need a 'scope to test it properly.
^ ^ This. The engine management unit controls the charge; it will usually only charge when the engine is on the over-run so it is difficult to measure any output from the alternator unless this can be replicated, or fooled into thinking it needs to produce an output.From what the OP says if he's getting 14v with the smart charge disabled then the alternator is probably working and the problem lies elsewhere. It will need a 'scope to test it properly.
tonyryan said:
BMI and EMU both reset, so far everything is running fine and no light. Thanks for the advice guys
I'd be interested to know exactly how this was fixed please?Edited by tonyryan on Wednesday 24th April 16:17
Just had a dead battery on a 2015 208, battery replaced now ok.
Battery goes flat again, voltage on terminals only around battery voltage, 12.x volts, never above 12.6.
Output from alternator always below 12 volt, disconnect the small signal wire from alternator and it goes uo to around 14 volt and charges battery.
Seems something in the smart system of this single wire is not telliing the alternate to generate!
I am having the exact same problem. 65 plate 208 and that's twice now that the car is dead when l need to go out. Don't have anything obvious that could be draining it. Only got it the day before lockdown so it's not been used much but it is weird that this is happening to others too🤔
Sheena Pritchard said:
I am having the exact same problem. 65 plate 208 and that's twice now that the car is dead when l need to go out. Don't have anything obvious that could be draining it. Only got it the day before lockdown so it's not been used much but it is weird that this is happening to others too??
The battery self-discharge and residual current from electronics will typically drain a car battery in about a month if everything is in good working order. It could be less if the battery is tired or the residual current is higher than typical. Once the battery is discharged it takes hours of driving to recharge it and if you are making shorter journeys you may struggle to recover the charge needed to start the engine let alone put any nett charge into it.Gassing Station | Home Mechanics | Top of Page | What's New | My Stuff