Does not start first time and battery draining over night - 2003 156 JTS

[156and33]

Hi

I have two possibly related issues, wonder if someone has a clue as to what is the problem or how to investigate.

Battery drain issue:  battery is in good condition (load tested).  When installed in the car the battery drains to 12.3v over night so I am keeping it on a charger.  When the interior lights are on and doors are closed battery current is 10s on milliamps.  When the lights go out, current draw from the battery goes up to 1 A.  I do not believe  there are any ignition relays in this car so am stumped as to what the cause might be

First start of the day:  the car fails to start every morning first go.  It usually starts OK immediately afterwards, and starts OK for the rest of the day.   It drives OK and I have no fault codes logged.  I used Multiecuscan to check: cranking RPM for crank sensor function (recently replaced), low and high high side fuel pressure (7 and 50 bar).  I have used a COP probe and each plug is getting a spark signal OK when running (still to check this during the first crank).  Any ideas?

Thanks
Duncan

[Mick A]

I reckon you could possibly have a problem with the key reader/immobiliser somewhere. Check when you say it cranks but won't start in the morning if the little key/lock symbol stays on the display between the tacho and the speedo binnacles.

A good auto-elec should find a current drain like that pretty quickly though.

[156and33]

Key light goes out normally

I am replacing all the fuses with the newer type so I can check for the parasitic current on each circuit without having to full the fuses.

I think that the issue is not strictly associated with the first start of the day, although I do have the problem always first start.  Needed a second crank this afternoon.  That was a red herring perhaps.

[Craig_m67]

Any ideas?

There is a well known issue with the bulb check circuit which is located on the tacho PCB. 

Have a read /Google.  If you know somebody with a known good tach, perhaps swap them over and see what happens (they're engine specific, easy to remove/refit tho). 

( Or just disconnect the tach and see what happens to the current drain? )

https://www.alfabb.com/threads/removing-the-stupid-bulb-warning-light.678792/

[156and33]

For some time the bulb light on the dial flickers when starting, is this what you mean?
Neither brake lights or number plates bulbs (2j are blown.