Charging system question (vectra C content)

[scaryoldcortina]

Well, strictly speaking it's a saab 9-3 not a vectra, but saab don't list a wiring diagram on autodata where vauxhall do.... it's a 56 plated 1.9TiD

 

Here's the situation, anyway. Recovered car from roadside - flat battery. Fitted fresh battery, checked charge with engine running, 11.4v so not charging. Battery light on dash not illuminated, although it lit during the self test before starting, Info display warning of low screenwash but nothing else. While driving back multiple systems failed (ABS, TC, Airbag, Power steering and gearbox control) so I limped on slowly hoping to make it back to the yard before everything failed. Couple of miles later everything came back on and the car drove fine. Soon as I got back, I put the meter on the battery again - 13.6v and rising. Gave it some load (lights on main beam, heater blower on demist) and the voltage started to drop a little but not much. Code read reveals 2 ECUs talking on CANbus, no codes stored.

 

Charged the original battery overnight, drop tested it this morning. it's fine. Started the car, again not charging (around 11.5v) so I went off and used autodata to find a wiring diagram.... the D+ terminal on the alternator goes to the ECM, and the "charge" light on the dash is controlled by the dashboard module, no direct connection between the two.

 

Unplugged the D+ wire and connected it to Battery + via a small bulb, It behaves as expected - Light goes out when engine started, Battery starts to charge (13.6 at idle rising to 13.9 when revved). Because of the unplugged wire, the charge light on the dash illuminated when I revved the car and the info display reads "Not Charging, make a safe stop". Scope on the battery shows the alt outputting rectified 3 phase with no "gaps"

 

SO.... my question. I'm wondering about the not charging but not warning situation, is this normal behaviour? The ECU clearly controls the alternator, and decides when it should/should not be charging, but the alt doesn't appear to be faulty and neither does the battery despite the fact that the car broke down. I'm tending towards a faulty alternator anyway, but I want to be fairly sure because it is very expensive AND a total pig to change.

[ashmicro]

I (and Cav) have the Poxhall/Awful dealer shizz. Is there anything on that I could look up for you?

[scaryoldcortina]

Yeah, if there is anything on the charging system and specifically how do you test for a faulty alternator when the ECU can switch it off when it feels like it I'd love to see it. I suspect tonedepear will also be interested (it's his car....)

[ashmicro]

Right. I have no idea what lamp H1 is. This is the General Electrical Troubleshooting part for a 2006 Vectra with that engine. I'm afraid I'm a bit wooly headed at the minute due to being full of Disprin and antibiotics. I'll post the pictures in a minute.

 

 

 

 

Easy diagnosis and trouble-shooting

 

Voltage measurement with digital multimeter

 

Fault symptom:

 

Lamp H1 does not illuminate.

 

Pre-condition:

 

 

Battery voltage OK, fuse OK, bulb OK. Set digital multimeter to V DC (direct voltage).

 

1st measurement:

 

Voltmeter indicates more than 11.5 V: circuit OK up to this measurement point.

 

No indication or indication too small: lead interruption or contact problems between fuse F2 and wiring harness plug X1.

 

2nd measurement:

 

Voltmeter indicates more than 11.5 V: circuit OK up to this measurement point.

 

No indication or indication too small: lead interruption or contact problems between wiring harness plug X1 and lamp H1.

 

3rd measurement:

 

Voltmeter indicates more than 11.5 V: lead interruption between lamp H1 and ground.

 

 

 

 

 

Resistance measurement with digital multimeter

 

Fault symptom:

 

Lamp H1 does not illuminate.

 

Pre-condition:

 

 

Battery voltage OK, fuse OK, bulb OK. Set digital multimeter to W (resistance), fuse F2 pulled (during the resistance measurement, current must not flow through the lead being measured).

 

1st measurement:

 

Ohmmeter indicates less than 2 W : circuit OK up to this measurement point.

 

Indication too large: lead interruption or contact problems between fuse F2 and wiring harness plug X1.

 

2nd measurement:

 

Ohmmeter indicates less than 2 W : circuit OK up to this measurement point.

 

Indication too large: lead interruption or contact problems between wiring harness plug X1 and lamp H1.

 

3rd measurement:

 

Ohmmeter indicates more than 2 W : lead interruption between lamp H1 and ground.

[ashmicro]

Voltage measurement

 

 

 

Resistance measurement

 

[scaryoldcortina]

Lamp H1 is the charge indicator on the dash, and it DOES illuminate during the self test. What I need to know about is the expected charging voltage at idle, and under load.

 

ps, I sympathise about the cold.... I feel like shite right now and I got soaked to the skin in torrential rain (with my head down the back of a saab engine...) this afternoon. I'm going to hide in front of the fire and complain all evening.

[ashmicro]

Ah, ok, I'll have a root around on this and see if I can find any figures. The layout of the Vauxhall Workshop Info System IS FUCKING SHIT.

[tonedepear]

  ashmicro said:

the Vauxhall electrical System IS FUCKING SHIT.

 

Efa

[ashmicro]

Right. It's told me to use "Vauxhall Field remedy 2513 - Battery and alternator testing". Can I find the bastard? Can I fuck as like. I'll have another look after I have some grub.

 

EDIT: Sorry lads, it's not in this. If I go to engine>Engine aggregates>electrical faults, it just send me back to the start. There's no actual bulletin. Fucking GM.

[Albert Ross]

WellI tried to get into Channel 21 and thence into TIS2WEB, but my connection isn't clear for the latter to work. If I get a chance at work tomorrow, I will try.... it might need a software update.

[tonedepear]

Thanks Albert/Ash. Sorry if I'm getting you pneumonia Scary.

[scaryoldcortina]

Thanks from me too (I've been out all evening playing guitar and not worrying about vauxhalls) You've already been more helpful than my local dealer who hung up on me when I said it was a saab and tried to sell me an alternator when I pretended it was a vectra.

[red5]

99.9% that the alternator ist kaput.

 

Pretty sure that every C 1.9 has had one by now - can't see SAAB's being different (correct me if I'm wrong...)

 

Soz.

[Rocket88]

Had similar bollocks to this on a Renault Megane big arse a couple of years ago. With fully charged battery it would start, and then stall 10 seconds later, and then wouldn't start again until battery was fully charged. It WAS the alternator..........

[Akron]

The alternator might be coded to the vehicle as well, so genuine new parts as well for ease

[Rocket88]

Also worth mentioning that a lot of modern stuff won't tolerate el cheapo batteries that aren't of the right output......

[scaryoldcortina]

I don't think it's coded. The only communication between the ECU and the alternator is taking the D+ wire from ground to battery voltage when it wants to charge. Also it's a GM branded battery that charges and drop tests fine, it's the right one for the car.

 

Based on a strange smell/noise last week and all the low voltage electrical messing around it's doing, a new alt is on order, I'll be fitting it tomorrow. It had better work!

 

 

Also, I just got a call from a local garage who want me to look at a vectra C 1.9DTi that won't charge the battery.......

[tonedepear]

Fingers crossed!

[scaryoldcortina]

You can uncross them now, it was the alternator.

 

For future reference - the new alt goes straight to 13.8v after a couple of seconds not charging straight after starting, rises to just short of 14v when revved, does not drop at all with the lights on. Also, to get the alternator out of the engine bay you need to remove the driver's side driveshaft because otherwise there isn't a big enough hole to pass it through.

[cobblers]

  scaryoldcortina said:

to get the alternator out of the engine bay you need to remove the driver's side driveshaft because otherwise there isn't a big enough hole to pass it through.

 

Sweet jesus.

[cort16]

I was involved in getting one of these out a Vectra (I was the hands) and we managed to get it out round the back of the engine by taking the fuel filter off the bulk head.

It really wasn't easy and required furious swearing.