I had to replace the Mass Air Flow sensor in my daughter's car (1st time I ever fixed something the first time with no issues!) I ended up disconnecting the battery when I did this (not sure if I had to or not) but now the instrument cluster lights are not coming on. The perimeter lights on the instrument panel (seat belt, high beams, battery, etc.) all work but the ones that illuminate the speedometer do not. I checked fuses below the steering column and also ones by the battery but all were good. I even took the dash apart (breaking the gear indicator in the process) and the bulbs appeared to be good. When I try adjusting the dimmer by the light switch, I can make the interior lights come on but the instrument panel still does not illuminate around the speedometer. I'm really at a loss here, plus I need to fix the gear indicator now! Any advice, other than taking it to a garage, would be greatly appreciated.

 

Just trying to guess and replacing parts can lead you into a rabbit hole.

Suggestion,,,,,,,,,,,,,, get a test light and start from the dimmer sw with the parking lamps on and find the color wire that responds to whatever dimmer setting you choose and trace that color wire up to the inst cluster. If it has power there it may be either the bulbs or the printed circuit in the cluster. Don't overlook something simple like a ground wire connection for the cluster . Start with the ground from battery negative terminal to the sheet metal in the engine compartment.l