Possible charging fault cause

[devilmaycare]

The battery seems OK, looking at cranking volts and no starting difficulties.

[Pappajohn]

Originally Posted by Simon@thecustom300cshop

The flickering lights could just be the alternator struggling to keep the voltage up whilst the heater is on. I think pulling fuses is worth a try. Does the code reader your waiting for do more than just engine codes and running functions?

really not sure until i get it Simon.

[Pappajohn]

Originally Posted by badgx

Can you be sure the mechanic replaced the alternator? Does it look new or just cleaned and serviced up?

Check & top up distilled water at your batteries, whilst a solution is found

definitely replaced as i did it myself

battery was checked a couple of weeks ago, needed a little water but very little and its an 800cca tested at 675cca @around 12v when the alternator was failing.

[devilmaycare]

Originally Posted by jackwalton

I always thought the regulator was in the Alternator too, but it appears that the ECU does the voltage regulation according to w/s manual.

Unless there is a regulator in the Alternator and the ECU does the final logic control depending upon which devices are turned on ??

Jack

The "standard" alternator does incorporate a regulator, but maybe the ECU also plays a part.

Some more diagnostic suggestions:

1. The cabin heater should only be energised when the engine is cold. Check water temp reading to confirm temp sensor is OK. Also, check ambient (air) temp on EVIC in case this also plays a part.

2. The following fuses relate to the cabin heater:

a) Front Engine Compartment: Cavity #14, 25A Clear, Cabin Heater/Engine Control Module (ECM). This fuse controls the relays, which switch the 3 heating elements.

b) Rear PDC (near battery): Cavities #1,2,3, 50A Red, Cabin Heater (each of 3 elements fused separately).

I think I would just try pulling fuses #1,2 and 3, which should completely disable the heater to confirm whether this is the culprit or not.

Correction to 2b: Location is under cowl cover at front.

[Pappajohn]

Originally Posted by devilmaycare

The "standard" alternator does incorporate a regulator, but maybe the ECU also plays a part.

Some more diagnostic suggestions:

1. The cabin heater should only be energised when the engine is cold. Check water temp reading to confirm temp sensor is OK. Also, check ambient (air) temp on EVIC in case this also plays a part.

2. The following fuses relate to the cabin heater:

a) Front Engine Compartment: Cavity #14, 25A Clear, Cabin Heater/Engine Control Module (ECM). This fuse controls the relays, which switch the 3 heating elements.

b) Rear PDC (near battery): Cavities #1,2,3, 50A Red, Cabin Heater (each of 3 elements fused separately).

I think I would just try pulling fuses #1,2 and 3, which should completely disable the heater to confirm whether this is the culprit or not.

not disagreeing with you, but my handbook says the diesel specific cabin heater fuses are under the cowl cover next to the brake fluid reservoir....3 x 50amp.

a job for another day.

[Simon@thecustom300cshop]

Originally Posted by Pappajohn

not disagreeing with you, but my handbook says the diesel specific cabin heater fuses are under the cowl cover next to the brake fluid reservoir....3 x 50amp.

a job for another day.

I don't know about fuses but there are some relays in there on CRD's.

[devilmaycare]

Originally Posted by Pappajohn

not disagreeing with you, but my handbook says the diesel specific cabin heater fuses are under the cowl cover next to the brake fluid reservoir....3 x 50amp.

Apologies! You are absolutely correct. I was mislead by the page heading (Rear PDC) and the photos (which did not include cowl cover), although I should have been suspicious of such heavy fuses being so far removed from the component they were protecting.

[Pappajohn]

maybe have a look tomorrow if SWMBO has nothing else planned

[badgx]

Originally Posted by Pappajohn

definitely replaced as i did it myself

battery was checked a couple of weeks ago, needed a little water but very little and its an 800cca tested at 675cca @around 12v when the alternator was failing.

OK, then the only last thing you could check is the headlight switch, that's for the flickering you mention to the dash and lights.

I found this thread, you may want to pm FISCH to see how he got on with the switch

Lighting issues - started going off and on...

[Pappajohn]

Originally Posted by badgx

OK, then the only last thing you could check is the headlight switch, that's for the flickering you mention to the dash and lights.

I found this thread, you may want to pm FISCH to see how he got on with the switch

Lighting issues - started going off and on...

thanks for the heads up and link but i doubt it's the switch.

the dash lights dont go out and on again....more like one second they get full voltage then next second they are getting 6 volts then back again next second and so on until the engine is warmed up and voltage increases again to 14+ volts which points me to the 'cold' engine electric heater elements pulling a very high current until the engine temp sensor tells them to turn off.

if i don't use the heater at all until the engine is up to normal temperature then everything works fine, 14 plus volts and no lights flickering, so i still suspect the heater, or more specifically, the electric cabin heater.

the cabin heater has 3 separate elements totalling 1000 watts (1kw), all controlled by 3 x 50amp fuses...if they all draw a max 50amps then thats around 80% of the alternators maximum output.

next job is remove the scuttle/cowl cover and pull the 3 fuses to see if that cures it.
if it does then the fuses will remain out.

never had a car with 'part time' electric heating so i wont miss it.