Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

1992 Miata - Indicator light fuse keeps blowing

Any ideas why I keep loosing my indicators (flashers). I initially thought it was dampness related, but in the 4 weeks I have had the car on the road this year (I live in NH) I have replaced the fuse 4 times, so the occurrences have escalated. Thinking it is an electrical short, but don’t know how to start diagnostics.

The easiest thing to check is whether one or more of the bulbs is not the type that is supposed to be used. If the bulbs turn out to be the correct ones, then I would check for damaged wiring–perhaps in the trunk. If you have a tiny area of insulation that has been cut or chafed, that wire could be shorting out on adjacent sheet metal. If that possiblity proves to be negative, then you have to begin searching for a less obvious short circuit.

Thanks - we bought the car as new back in '92 so know the bulbs are still the originals. Maybe a weekend job for hubby and I to check out the wiring.

To help find the shorting problem it would help to know if the fuse is only blowing when selecting the left or right direction, or either side. The problem could be near the lighting on one side or the other. It could also be in the steering column. If the turn signals and brake lights share the same bulb, which is usually the case, and the brake light circuit isn’t having any trouble, the trouble may then be with the wiring to one of the front turn indicator lights or in the steering column.

Diagnostics will be tough as the fuse can last 1 day, 1 week or a month then wham it blows again. I try to monitor my actions but you don’t know it has blown until you next try to indicate and its gone - which is usually on the next trip or return trip. It does appear that only the indicators are affected.

Do your best to look at all the wires involved to see if one is damaged.

replace all the light bulbs. front, back, stop and turn. (not the headlights)

after this many years the bulbs wear down the contacts and its typical to short out at the bulb socket itself.