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Electrical issues after alternator replaced


faultrd
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Hi all, hoping someone can point me towards what may be causing an issue I'm having.

I recently had a breakdown, and after the breakdown company attended, they diagnosed a faulty alternator. They got me going again but decided that due to them not knowing if it may cut out, that they would prefer to tow me, so I was towed to the garage. The garage replaced my alternator the next day and all seemed fine. But I have started to notice some small issues. The radio does not keep the date and time. The avg miles per gallon and avg speed displays are all reset to 0 after every trip. The fuel meter always shows the amount of fuel in the tank (usually shows below 0 when the key is removed). All the instrument dials flicker when the engine is turned on. There is a noticable delay when turning the key in the ignition, before the starter motor fires - used to be instant.

I spoke to the garage and they said it's nothing they have done, and that replacing the alternator would not affect this. They did however say that if an alternator dies, and you are jump started (which i was) that it can possibly damage the PCM. I don't know if that's true but would like someone elses opinion on what could be causing these issues? 

 

Cheers

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Sorry I should have said, it's a Focus Mk2, 57 plate. Diesel

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Hi get wiring check on alternator mate also could be running to much volt 

sounds like something not wired up right have a good look see if earth ect ok on battery as they should have disconnected this before repairs 

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59 minutes ago, Damien said:

Hi get wiring check on alternator mate also could be running to much volt 

sounds like something not wired up right have a good look see if earth ect ok on battery as they should have disconnected this before repairs 

Thanks I'll have a look. To be honest my battery is probably due a replacement in itself, could it just be down to that? Although there's no warning lights on for it. 

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When you alternator was goosed your battery won't of been charging just using what charge in there.

battery could be fine garage may have just had wire issue ie I would get them double check wiring to this and the battery.

funny only doing it since been replaced 

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Also your battery may have been disconnected while fitting alternator. Check the terminals on the battery are sound and well greased.

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4 hours ago, faultrd said:

All the instrument dials flicker when the engine is turned on

It sounds like the battery voltage is dropping badly when the starter motor is turned on. If you have a multimeter, you could check this. battery should be 12.4 to 12.7v with everything off, it should not drop below 8v when cranking, and should rise to about 14v to 14.4v a short time after starting. Garages, and some diy mechanics, have battery testing meters.

Batteries do not like being heavily discharged, they never fully recover. An older battery may not really recover at all. If when the car broke down, the alternator had stopped charging some time before, and the breakdown was due to the battery going flat, then that may well have killed it.

So check or replace the battery first, before suspecting electrical problems.

As regards jump starting, it is an approved procedure, it is in the Ford owners manual (mine anyway), and all Ford car electronics are designed to withstand odd voltages that may result. There may be a very few instances of pcms being damaged, but I think most of it is hype.

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13 hours ago, Tdci-Peter said:

It sounds like the battery voltage is dropping badly when the starter motor is turned on. If you have a multimeter, you could check this. Battery should be 12.4 to 12.7v with everything off, it should not drop below 8v when cranking, and should rise to about 14v to 14.4v a short time after starting. Garages, and some diy mechanics, have battery testing meters.

Batteries do not like being heavily discharged, they never fully recover. An older battery may not really recover at all. If when the car broke down, the alternator had stopped charging some time before, and the breakdown was due to the battery going flat, then that may well have killed it.

So check or replace the battery first, before suspecting electrical problems.

As regards jump starting, it is an approved procedure, it is in the Ford owners manual (mine anyway), and all Ford car electronics are designed to withstand odd voltages that may result. There may be a very few instances of pcms being damaged, but I think most of it is hype.

Thanks for the info. When I broke down, the RAC ran a battery test and the result of it was emailed to me afterwards. Here it is :

battery Test Results

battery Test

Battery Manufacturer: OTHER

Rating of battery tested: 600CCA

Chemistry of battery tested: FLOODED

Rated Ah of battery tested: 60

Smart charge: Yes

Battery Test Results

Time: 22/08/2016 17:03

Temperature: 39.4°C

Measured voltage: 12.06Volts

Measured rating: 198CCA

Reserve capacity: Poor Reserve

State of health: 31%

State of charge: 36%

Test Result: Replace battery


This is why I asked the garage to replace the battery aswell but they advised it wasn't needed when they checked it themselves. Don't know who to believe? But I'm going to get the battery replaced anyway and I'll report back.

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Update. Just replaced the battery with a brand new one, and the issues still remain, it hasn't fixed it. 

Also, another quirk I've noticed, the chime that should play if you leave the headlights on with the key out, doesn't play anymore. To me it's seeming more and more like a computer problem. Might it just need a reset? I think I'm going to take it to a garage and get the codes checked next.

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1 hour ago, faultrd said:

To me it's seeming more and more like a computer problem. Might it just need a reset? I think I'm going to take it to a garage and get the codes checked next.

That is a ... shame. The only clear link between the symptoms, especially things like radio, was low supply voltage.

I would still further investigate the supply wiring, earth connections, and main supply connections around the engine bay fuse box area. But it looks like not being an easy to find fault, now.

Regarding electronic problems, the fault list is rather scattered:

The lights on chime: Lights on is detected by the BCM (aka GEM, part of the passenger fuse box), but the chime sounder is in the IC (Instrument Cluster). MS-CAN bus is used to convey the signal.

Radio Time & Date: This is normally pretty autonomous, but a Ford radio is connected to the MS-CAN bus, which links to the IC and the BCM.

MPG & Avg Speed: Done in the IC, but it gets its info from the ABS (if fitted) over the HS-CAN bus or a Vehicle Speed Sensor.

Fuel Gauge: Local to the IC (gauge & tank sender connections)

Other needles jumping: Local to IC.

Delay on start: Communications on the HS-CAN bus between PCM & IC (for PATS authorisation). Also possible data transfers over MS-CAN from the BCM.

Any other little quirks or oddities? And are all these still present? Does the seat belt chime work?

The one module that features in all the above is the IC. But I think I would remove the radio first. It could just be corrupting transfers over the MS-CAN bus. And radios may not be designed to quite the same standards of robustness that the other units are supposed to be.

It will have to be a good garage, with Ford IDS, and people who really know how to use it, in order to get a decent diagnosis without going down the line of replacing yet more expensive bits. I would use Forscan on the car, it can read and do most of what the Ford IDS system can. But it is unlikely give results clearly indicating the culprit. It is often not quite that easy!

At least the battery was probably not a waste of money, the RAC report is probably accurate in saying it was nearing the end of its life. Just not causing this set of problems.

 

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1 hour ago, Tdci-Peter said:

That is a ... shame. The only clear link between the symptoms, especially things like radio, was low supply voltage.

I would still further investigate the supply wiring, earth connections, and main supply connections around the engine bay fuse box area. But it looks like not being an easy to find fault, now.

Regarding electronic problems, the fault list is rather scattered:

The lights on chime: Lights on is detected by the BCM (aka GEM, part of the passenger fuse box), but the chime sounder is in the IC (Instrument Cluster). MS-CAN bus is used to convey the signal.

Radio Time & Date: This is normally pretty autonomous, but a Ford radio is connected to the MS-CAN bus, which links to the IC and the BCM.

MPG & Avg Speed: Done in the IC, but it gets its info from the ABS (if fitted) over the HS-CAN bus or a Vehicle Speed Sensor.

Fuel Gauge: Local to the IC (gauge & tank sender connections)

Other needles jumping: Local to IC.

Delay on start: Communications on the HS-CAN bus between PCM & IC (for PATS authorisation). Also possible data transfers over MS-CAN from the BCM.

Any other little quirks or oddities? And are all these still present? Does the seat belt chime work?

The one module that features in all the above is the IC. But I think I would remove the radio first. It could just be corrupting transfers over the MS-CAN bus. And radios may not be designed to quite the same standards of robustness that the other units are supposed to be.

It will have to be a good garage, with Ford IDS, and people who really know how to use it, in order to get a decent diagnosis without going down the line of replacing yet more expensive bits. I would use Forscan on the car, it can read and do most of what the Ford IDS system can. But it is unlikely give results clearly indicating the culprit. It is often not quite that easy!

At least the battery was probably not a waste of money, the RAC report is probably accurate in saying it was nearing the end of its life. Just not causing this set of problems.

 

Yeah the seat belt chime works, but that only occurs when the car is on and once the car is on everything works happily enough. It's just when first starting up, and when turned off that the issues seem to be. I've made a small video to show in more detail what the issues look like. I'm just uploading it to YouTube now. I'll stick the link in here when it's done. 

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Heres a vid showing exactly what happens. Shows radio resetting back to default date and time, dials jumping around and not resetting back to 0. See what you think. 

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1 hour ago, faultrd said:

dials jumping around and not resetting back to 0

The dials problem has to be instrument cluster, or the power supplies to it.

The dials are driven by little stepper motors, so only move when commanded. On my car, all four dials are driven to below zero when the ignition is turned off. This is the physical end of the stepper motor travel. On ignition on, they bump against this end stop a couple of times, then move to the correct locations. (The reverse movement is to calibrate them, in case they have moved accidentally out of position while the ignition is off).

So a problem is also happening on your car at key off time, as well as key on.

The IC gets 3 12v supplies:

Permanent battery via fuse F46 (10A)

Ignition 12v via fuse F67 (10A)

Aux Supply 12v via Fuse F68 (7.5A) (This has power in Ignition positions 1 & 2, not in 0 or Crank.)

The radio gets the Aux supply (F68) power, and a permanent 12v via F58 (15A)

Worth checking these fuses (in the Passenger fuse box), If they are ok, I would check the supplies at the IC connector, then I would investigate internal problems in the IC, or send it for repair.

 

 

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Bet it's a fuse gone have read this fault on another forum after alternator replacement these problems 

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Thanks I'll have a check of the fuses in the morning. 

Peter thanks for all the great info in your posts. You certainly know your stuff!

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12 minutes ago, faultrd said:

Thanks I'll have a check of the fuses in the morning.

At some point, I think it was the Mk2 to Mk2A change, the design of the fuse box changed, and the fuse numbers changed to ones over 100. The Mk2 fusebox has most of the fuses in two long rows along the front, as in the pic. But I think most of the wiring remained essentially the same. Post here if you have the later fusebox.

I may know some stuff, and I have dismantled & repaired one of those ICs, but there is an awful lot more that I don't know!

Peter.

Mk2-BCM.JPG

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12 hours ago, Tdci-Peter said:

At some point, I think it was the Mk2 to Mk2A change, the design of the fuse box changed, and the fuse numbers changed to ones over 100. The Mk2 fusebox has most of the fuses in two long rows along the front, as in the pic. But I think most of the wiring remained essentially the same. Post here if you have the later fusebox.

I may know some stuff, and I have dismantled & repaired one of those ICs, but there is an awful lot more that I don't know!

Peter.

Mk2-BCM.JPG

Thanks Peter, my fuse box was indeed different and all started in the hundreds. Regardless, with the info you gave I was able to check the relevant fuses and indeed one had blown. It was 107 - Instrument cluster battery supply (10A). Seems so obvious now :) I had only checked the radio one as the radio time/date was the first symptom I noticed. All working fine now. Thanks very much for the help, really appreciate it. Hopefully if anyone else has this issue they can see what to do now.

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