My 1978 fj40 radio (aftermarket) went out. Then I looked down and my gauges (oil, temp, fuel) were all going down to zero. The truck runs perfectly fine other than that. The first thing I did was check the fuses and the heater fuse was blown. I replaced that, checked all the other fuses with a meter and tried again. I don't know if it's pertinent, but the seldom used heater sometimes needed to be turned off then on to get to blow. Anyway, still no gauges, radio, or heater. What am I missing? Some forums mention the heater blower motor resistor (which I ordered), but that only seems to be for temp and fuel gauges. There's no other problems or malfunctioning electronics. If this has been posted before, can you post the link?