Advice from Civinfo forum from someone's unforunate experience:-

"Just thought i would post a story of the fiasco i've had this morning...

To cut a long story short I was a div and left my lights on last night. Tried to jump start to car this morning, and the immobiliser light came on and stayed on - so although the car turned over, it wouldnt start.

Cue the AA, towage to my local Honda dealer, and following a short conversation with the Mr Man at Honda, i became aware of a serious fault.

If you connect the jump leads to the battery with the key in the ignition, the immobiliser scrambles and shuts down, meaning that Mr Honda needs to plug his computer into the car to get it started again. Therefore the moral of the story is:

***Make sure your keys ARE NOT in the ignition before you connect your jump leads to the battery!!!!***"

Apparently Honda are aware of this, but have failed to inform anyone about it. Nice one!!!

And the technoblurb for this from a Honda Tech is:-

"This problem only affects 2006 5dr cars only,When the ignition keys are left in the ignition and jump leads are connected to the vehicle it causes an electrical disturbance (chattering) to the +B voltage, this disturbance causes a problem with the data within the EEPROM. The MICU sees the data problem and re-writes the whole EEPROM contents which also overwrites the key, when you try to start the car the immobiliser does not recognise the key and prevents the engine from starting.
All 3dr cars & all those built from the end of 2006 should not be affected as the eeprom software has been made more resistant to electrical disturbance when jump starting !<*** title="Cool" class="inlineimg" src="http://www.civinfo.com/forum/images/smilies/icon_cool.gif" border="0" alt="" />