The Plot Thickens ... (mystery parasitic battery drain)

[Lazy_Oaf]

Hi Folks,

Got a bit of a mystery on my hands and it's so far left 2 RAC techs and a local garage absolutely baffled.

10 Days ago I bought a used 2004 Ford Fiesta 1.4 TCDI, drove great, everything worked great, smelt nice so of course I bought it happy as larry.

Suddenly one morning without warning the battery was completely flat, thinking i'd maybe just left a light on I called the RAC for a jump and a quick diagnostic test. Ended up forking out £130 for a swanky big ol' silver calcium battery, the one in the car was a dinky little lion battery that clearly wasnt fit for purpose. RAC didn't detect any abnormal battery drain (apparently) so bosh, a blip on my otherwise perfect little new car, onwards to glory.

2 Days later, dead battery again, RAC comes back out, jumps, tests, suddenly there's a 1Amp drain on the battery after 45 mins of the car being completely switched off.

Whipped out the ol' multi meter and started pulling fuses to see what was causing such a drain and I noticed something pretty odd ...

https://Upload the image directly to the thread.com/a/UbKedd5

Here's the fuse box diagram on the back of my glove box, note top left of the diagram, slot R10, battery saver - you'll notice the actual relay module is missing on my car

Oddly all of my interior lights / clock / displays all work as they should even with this missing

Could this be the cause of my mystery drain? I've pulled most of the fuses out and nothing seems to stop this drain

Has anyone ever come across something like this before? Any help / advice or similar stories would be greatly appreciated

 

[Lazy_Oaf]

Working images, sorry

 

[static zap]

Check for signs of alarms added ,constant lives on stereos.
my less substantial drain was a relay ,
miss wired in lighting circuit ..but that was a Ford a long time ago .
(relays present so lighting stalk did not burn up) ... Sorry nothing more specific for your model ! (Could even feel relay warmth in winter !)

 

[Squid]

As Static Zap mentioned, it's the aftermarket alarm/stereo installalers that butcher the wiring looms which a few years down the line cause issues, also check the earths and for any frayed cables especially the loom that cause from body to door as well as the loom through to the hatch.

I used one of this to whittle down a parasitic drain on my E30 (its was the aftermarket alarm)

https://www.amazon.co.uk/dp/B001SBP...=9045939&hvtargid=pla-421592008210&th=1&psc=1

If you have a Fluke/meter you can also get the leads for it.

https://www.amazon.co.uk/Gunson-770..._rd_t=40701&psc=1&refRID=AWB2QD9RSSMJQQBV0CNG

 

[Marvo]

I think the battery saver socket is for a relay that automatically operates several minutes after the ignition is switched off in order to turn of internal items that may have been left on by accident. Not sure exactly which items but usually interior lights, glove box light, maybe boot light etc. The battery saver....or lack of it won't be causing the drain.

 

[Marvo]

As mentioned aftermarket things like sat navs, GPS, alarms/security items, dash cams are the likely culprits.

 

[Deleted member 26818]

When you park the car, is it flat or at an angle (two wheels on the pavement , two wheels on the road)?

 

[Squid]

When you park the car, is it flat or at an angle (two wheels on the pavement , two wheels on the road)?

Modern batteries are sealed so its not that type of "leak" ;o))))

 

[static zap]

Had a puddle in a Pug , that upset more things
parked leaning a certain way.
(and a musty Escort)

When you park the car, is it flat or at an angle (two wheels on the pavement , two wheels on the road)?

 

[Squid]

Just had a look on the net, seems to be an issue with certain Fords, alternator and rectifier could also be failing.

 

[Daryl Crooks]

Was this problem fixed?