G'day all
The AU fairmont
About 3 weeks ago my wife visited her mum and when she went to leave there was no electrical activity at all.
My first thought was how could she flatten the battery to the stage that even the interior light would not have some form of glow.
A couple of hours later I got there to find nothing was working but the battery was ok.
For some reason I remembered reading somewhere that a blown fuse may stop the car starting ( interior light rings a bell ). Since I had no idea which one that was so I had her pull and check each fuse while I looked for loose wires on the ecu ( passenger door ). after a few minutes I noticed the interior light was on and the car would start.
Confused to say the least. I told her to take my car until I find a cause. For about a week I drove the car a few times locally with no problems.
Then she wanted to take it to her mums and guess what it would not start ( I laughed ).
This time the electrics were fine i.e. the starter would turn over but it would not start on petrol. I changed it to LPG and it started fine. Went back to petrol and it started.
Forscan shows everything ok
Except --module BEM has no DTC function
Is this normal as I have just started to use Forscan?

Any ideas of where to look would be appreciated
Dave

When the problem occurs is there a flashing hand idiot light on the dash? count frequency of the flsh if that happens & ask here, people know how to interpret what that means ... your BEM is probably failing, it's common at this age, mine went bad about 1.5yrs ago, similar symptoms as yours has displayed
There's a company that does exchange reco units, second hand not worth the hassle, the plastic case are colour coded to differentiate different model units, about $400 with a deposit system if you want them to send a new one before they receive the failed unit, if you can't pair the ECU with the BCM/BEM you'll need someone with a good enough scan tool & knows how, they aint straight forward, mine got towed to the local auto electrician after I swapped mine, he's a good car sparky but needed a guy with experience with the AU to walk him through it, make sure they pair both keys to the new unit before you leave, if either key starts the car then the car stalled after starting, they have missed pairing that key.

https://www.youtube.com/shorts/ckUIi5f_cwI