RPTR LOSES CTL OF ACFT ALT DURING ATTEMPTS TO READ APCH PLATE WITHOUT COCKPIT LIGHTING.

Narrative

DEPARTED XA:15 HRS EARLIER AFTER FULL DAY OF CAMPING AND HIKING. IMC ALMOST ENTIRE ROUTE HOME. AUTOPLT INOP; THINK I WAS TIRED. FIRST NIGHT FLYING IN ABOUT 9 MONTHS. ON WAY OUTBOUND THE PREVIOUS DAY; NOTICED DOME LIGHT LEFT ON BY PREVIOUS PLT. TURNED OFF. IT TURNS OUT THE C182 HAS A TOGGLE SWITCH THAT ILLUMINATES EITHER PANEL POSTS OR THE DOME FLOOD LIGHT. DIDN'T DETERMINE THAT UNTIL I LANDED. TRIED SEVERAL TIMES ON WAY HOME TO GET DOME LIGHT ON -- UNSUCCESSFUL. FLYING SOLO; NO ONE TO HELP WITH LIGHTING; MONITOR AND CHK ALT; ETC. THE PROB WAS THAT I HAD A FLASHLIGHT STRUNG AROUND MY NECK I WAS USING TO ILLUMINATE THE APCH PLATE ON THE YOKE CLIP. AFTER BEING CLRED FOR THE VOR-A INTO 7D2; I WAS RECHKING INITIAL ALT; WHILE FINISHING THE TURN ONTO THE VOR RADIAL (124 DEG). IMC AT THE TIME. COULDN'T GET FLOOD/DOME LIGHT TO WORK; SO HAD HEAD DOWN AND WAS HOLDING FLASHLIGHT TO SEE. NEXT THING I KNOW; I LOOK UP; SEE LIGHTS OF GND; IN ABOUT A 35-40 DEG L BANK; ABOUT 600-700 FT BELOW MINIMUM ALT FOR THAT SEGMENT. RECOVERED; INITIATED CLB (BACK INTO IMC) JUST AS DTW APCH ASKED FLT CONDITIONS (REPLY IMC) AND THEN SAID CHK ALT. STILL OUTSIDE PERLS INTXN. FLUSTERED; I FLEW THE REMAINDER OF THE APCH FINE. LESSONS: GET LIGHTING SET UP BEFORE CRITICAL APCH PHASE OF IFR FLT; KNOW YOUR PLANE. MEMORIZE APCH ALTS; FIXES ON PLATE EARLIER IN FLT. KEEP SCAN UP WHILE LOOKING AT PLATE AND CHART. ONLY TOOK 15 SECONDS OR SO TO GET THIS FAR OUT OF CTL; WHAT IF LOWER CEILING WAS IN PLACE; WOULD I HAVE RECOGNIZED SIT IN TIME TO RECOVER?