Athame1

iTrader: (2)

Hi all,

On my05sti uk the petrol low warning light keeps coming on even with a full tank, goes off after a while but can come back on

pulled p2503 error code "Charging System Voltage Low"

checked battery v 12.6

checked alternator v14.8

Do you think the petrol light problem is connected to code error stored? ( eml is not on )

Jump to post 15 for new question (thanks)

Don Clark

Possibly one of the two sender units in the tank is damaged or float punctured..............




or a bad electrical connection...............

Athame1

iTrader: (2)

Does the switch for the petrol light have its own float ?(petrol gauge seems OK)

and would that bring up the error code I'm getting? or have I got two problems

Thanks

Mark

Dan-

my light doesnt ever come on, not with the ignition or when needle hits E driving 600 miles to scotland i filled up everytime i got to quarter but i couldnt 1 time and the needle hit E with no warning light and was a scary drive to find a fuel station !!!

Don Clark

If the level gauge is OK then it's possibly further up the chain possibly a fault in the Combination unit...............



The P2503 error code is one that is not listed in any of the Subaru Manuals I have not even the the MY11 Impreza.

Would clear the codes (including stored ones) and see if it comes back.








On a couple of my previous cars it didn't come on 'til way past E..........
Worth carrying a full petrol can around and do a test so you know.
"Usually" comes on with about 4-5 Litres left.

PhilWrx100

My light does come on but the fuel gauge needs to be really low, near empty. Also gauge low light will not illuminate up on ignition as power stays on the gauge and float i assume, due to the gauge staying live after ignition off. Well that's how my blob Wrx works anyway

PhilWrx100

Best not risk running out of fuel for a test as stated in manual "can cause damage to cats and turbo"

super_ted

iTrader: (30)

How can it cause damage??!!

Dan-

I never run my car down past quarter, just on that occasion I had nowhere to full up for miles, just would be nice to see a light that's supposed to illuminate with the ignition on all my other cars

martin850

iTrader: (51)

How many miles do you get once the light comes on?

Athame1

iTrader: (2)

never really let it go down to less than quarter of a tank

had never seen this light on until a few days ago

@Don Clark reset code came straight back,reset today,still ok
is the fault in the Combination unit a plug and play kind of thing (I'm at the limits of my understanding on this one )

googled p2503 Subaru odb2 and got "Charging System Voltage Low"

thanks

Mark

Don Clark

Not really got an answer for the low fuel light. Worth checking all connectors are clean and tight.

As for the code, worth checking the main earth connections and battery terminals are clean and vaselined.

PhilWrx100

it just says in manual "if the fuel is low it could result in the engine misfiring and as a result could damage the cat and turbocharger". I believe its the one in the uppipe(if you've got a Wrx) that could break up and fire into the turbo. Another reason why guys here change to a decat one(sti one)

Athame1

iTrader: (2)

@don Clark will do thanks for your time

Mark

Athame1

iTrader: (2)

More help please

Done the above and checked the senders in the tank, seem ok checked resistance moves when float moves.

Was ok for a few days but

Now the gauge reads half a tank all the time which is fun can anyone
Tell me where the combination unit is and how to check it ?

Thanks
Mark

Mcintyre19

I was down to the E today, no warning light and I filled up to the brim. Only 48 litres went in. So if there was still 12 litres left in the tank why did it read empty?

Athame1

iTrader: (2)

Ha,mine was the same🔼🔼 had never seen the light on
Now it comes on all the time. Plus I've always got half a tank ( needle stuck ) suppose at least my mpg seems great now

Mcintyre19

Braved it to see when it would come on. Only joking was a busy day event organising and I can only fill up from one station about 7 miles away.

Bob Rawle

P2503 is a valid Subaru code and is in the workshop manual, its not related to the fuel light problem. You need to take out the pump assemblies from both sides of the tank and check the sender units for correct operation also that the float on the pump side is not being fouled by any of the jet pump return pipework.

If you want to email me on rbr@brdevelopments.com I can email you some tech info to help.

Its normal for there to be about 10 litres left when on empty/light coming on.

cheers

bob