Battery drain

[wee_gus]

Guys I am having an issue with my van.
2014 VW crafter.

In the mornings she will be almost dead, tries to start, does a couple of spins and throws the towel in.

Today I checked what’s draining it, pulled the neg lead off the battery and put my meter on in it reading 1.45mA, pulled every fuse I could find and didn’t change reading.

Put the lead back on and started it. Let it run for 10 mins switched off, left for 10 mins and started it. Ran it for another 10 mins, switched off and opened side door, lights are on. 10 mins go to start and same as would happen in a morning. Have it a jump. Put my meter on AC and was showing 0.15 V Ac.

Could a faulty diode in alternator cause my issue, van charges spot on. It’s got me stumped..

I do have a reverse cam, beacons and work lights and a couple of marker lights but they all work off my aux battery that is fed via the main battery from a split charge relay

 

[Smiffy]

Guys I am having an issue with my van.
2014 VW crafter.

In the mornings she will be almost dead, tries to start, does a couple of spins and throws the towel in.

Today I checked what’s draining it, pulled the neg lead off the battery and put my meter on in it reading 1.45mA, pulled every fuse I could find and didn’t change reading.

Put the lead back on and started it. Let it run for 10 mins switched off, left for 10 mins and started it. Ran it for another 10 mins, switched off and opened side door, lights are on. 10 mins go to start and same as would happen in a morning. Have it a jump. Put my meter on AC and was showing 0.15 V Ac.

Could a faulty diode in alternator cause my issue, van charges spot on. It’s got me stumped..

I do have a reverse cam, beacons and work lights and a couple of marker lights but they all work off my aux battery that is fed via the main battery from a split charge relay

Have u checked the second battery voltage at the same time ?? To check the split charge is working correctly

 

[wee_gus]

Yes and was ok, wasn’t pulling voltage when split charge was off

 

[Diggerdavey]

Hi, what does the amp meter read if you close doors and leave for 15-20 mins once the CAN system has gone to sleep? These modern vehicles can take quite some time before all control units shut down. Also removing fuses can wake the network again giving some time between fuse removal before current drain stabilises. It’s better to measure Millivolts passing through each fuse to determine current flow. There is a chart on the net identifying amp draw by fuse size using the millivolt method. I’ll try and find a link and post it

 

[Diggerdavey]

I’m not able to post a link. But autologic do have a web page with the full fuse voltage drop method that may prove helpful

 

[V8Druid]

sounds like a canbus issue .... had a similar fault on a Fabia, couple of years ago and failed to trace it ... put an isolator in and Josh has been driving it everyday since, as his get to work bus with no issues ... as long as he isolates it, if left for any period of time.
Fabia showed very similar symptoms and had considered the alternator myself ... even changed it .... to no avail ... tried all sorts, but the car never went to sleep properly ... and always showed a drain ...... would kill a brand new battery overnight .... totally!!

P.S. .... said Fabia passed it's MOT friday .... again, much to Josh's amazement

 

[pettsy]

I assume the headunit is standard factory one?

 

[Gecko]

meter on in it reading 1.45mA

Just as a reality check, could you check your units? 1.45mA is less than nothing. Some dust on top of the battery could leak that much.
What I'm saying is; if you are confident the reading is ~1.45mA, it's telling you there is nothing wrong (at least when you took the reading).

Put my meter on AC and was showing 0.15 V Ac.

Across the battery with the engine running? That sounds plausible.

Try the volt meter across the battery before and after starting - you should see at least a 1V jump with the engine running.

 

[jd6820]

Just as a reality check, could you check your units? 1.45mA is less than nothing. Some dust on top of the battery could leak that much.
What I'm saying is; if you are confident the reading is ~1.45mA, it's telling you there is nothing wrong (at least when you took the reading).


Across the battery with the engine running? That sounds plausible.

Try the volt meter across the battery before and after starting - you should see at least a 1V jump with the engine running.

I'd agree with the above 1.45mA is sod all current bearing in mind the typical battery has a 80AH capacity. That's a lot of hours to run your battery flat.

 

[Smiffy]

If the canbus is playing up disconnect both battery leads and hold the together disconnected with no battery in place
I don't know the mechanics of it but it drains all residual voltage stored in the system and resets the computer

 

[wee_gus]

Was a duff battery, although the induction window said it was
Good and a battery tester said it was good, replaced and been perfect since

 

[Quattromike]

All's well that ends well ?

 

[james01]

That's really good if you got the solutions and fix it well.