intermittent electrical power loss

Question

Total electrical power loss for several microseconds, during idle engine may cut out. The problem is more pronounced on bumpy road surface. Battery connections and battery in pristine condition. Engine warning light comes on but clears after restarting. The situation is worsening gradually.

Answer 1

If the light clear you should have a code stored in the Engine Control Module. You should start by checking the code. There are many things that the cause the loss of power, harness connector, ground battery connection to body, ignition switch, etc. I suggest starting with the engine code.

Comments

Thanks,  OBDIITech. Of course you're right however, while I waited for an interface to enable me to read codes on my laptop, I checked some connections and relays in the main fuse box and in the process of reconnecting everything that I could test for voltage and resistance, the problem has now mysteriously vanished. I can't say for certain the fault's been fixed because I haven't been able to isolate it but I won't argue with the result.
specwiz

Answer 2

Had similar issue with a 1994 Honda Accord. Found that the rod holding the hood up would sometimes touch the battery ground wire and disable power.

Comments

*Problem solved* and not unlike your issue with the battery terminal. With all the electronic stuff on these models it only takes a slight momentary voltage drop to upset the system and that was traced to the battery negative terminal. No visible corrosion but just enough oxidation on the battery post to cause intermittent voltage drops.