I too have an intermittent Sat Nav problem. It was fine until my Tourer Exec jumped a cog on the timing in February (120k miles). Then 5 weeks and £2k later, after the top end was rebuilt, the touch screen was not booting up, though it might suddenly come on while I was driving after anything between 10-50 miles - but not always! Over the next 2 months the main dealer in Leeds, who did the rebuild, checked the car several times due to the Engine Management and VSA warnings being on as much as off, before asking me to leave it overnight. This time they offered a courtesy car - just over 2 weeks later I picked up the Accord and even though they had swapped the computer with one on loan from Honda UKHQ (and back again,) they stated that they had no idea what's causing the fault, but it had nothing to do with the work they'd done. They did manage to solve the EM and VSA issue though. This is a 2003 model, and I've been it's owner since 2004 without any hitch to the electrics. One thing I've got used to over the last few months is that I no longer pause with the ignition key. That is, if I partly turn the key so that the radio and Sat Nav comes on and then I start the engine, this causes the radio to momentarily cut out and the Sat Nav (or computer) to crash. Re-starting the car does nothing - but if I turn the ignition off for 3-4 minutes and then re-start, it usually boots up the touch screen & sat nav. Because the touch screen controls speakers, radio-presets, clock, etc. etc. this is more than a pure Sat Nav issue. Now that I have noted this technique it may help someone. For some reason, I believe the capacitors are not discharging properly unless I wait 3-4 mins, and this is somehow preventing a clean boot-up - the main dealer ***ures me that it is not an earthing problem. Any suggestions?
