Radio reboots when cooling fan on Jeep turns on

[mr_fx]

I have been driving in the city a bit as of late, and I have noticed that from time to time when the electric cooling fan turns on that the lights dim and the radio reboots

my guess is that the fan is pulling the voltage down on it's initial spinup (I think some have reported up to a 52 amp spin up from zero to full speed, but like 15 amps or less to keep it spinning...

anyways the fan and the radio are direct to the battery

well actually the fan runs to a nice bosche relay and a bosche temp sensor to key the relay... but you get the point

 

[Rb30]

That is way to much current for an automotive fan to pull on start up and run. May have a partial short in the winding.

 

[mr_fx]

That is way to much current for an automotive fan to pull on start up and run. May have a partial short in the winding.

lol I agree, but these are reports some people have claimed... I can tell you I have a 30 amp fuse on mine and a 30 amp relay... and the car that uses the same fan stock only has a 30 amp as well...

I seriously doubt the fan pulls that much, but hey who knows

 

[VE6SDG]

Elect fans DO draw almost that on start up. I had a 25 amp fuse in mine when I installed it in my Jeep and it blew the first time I turned it on. Got a 30 in there now and it's holding as long as I don't forget to turn in off for water crossings as the extra resistance will cause a currant spike and blow the 30 as well.

 

[mr_fx]

ok so then what can I do to correct reboot issue?

 

[VE6SDG]

How old is the battery? Maybe upgrade to a high output alternator and or high cca battery. Other thing to consider is doing what the 16 yo kids do with their stereos....put a cap in the radio circuit. It will store energy and give it to the radio when the fan kicks in and hopefully prevent it from a reboot.

 

[avistar23]

try a 0 gauge from the alt to battery, alt to chassi, battery to chasi, although the root of the problem is the electrical system not handling the surge, those 3 mods may raise the normal voltage enough to stop the reset problem on surge.

 

[mr_fx]

well I think I solved this issue

1.) cleaned top post battery terminals

2.) cleaned post connectors

3.) ran new ground from chassis to battery

4.) made a distrobution box that ties has a feed right off the battery and the alternator

5.) moved all the add on accessories off the battery to the distrobution box

now I have the heater and the engine cooling fan running full blast and no drop in voltage

In fact the voltage now sets about 14.2-14.6 at idle before it was more like 13.4-13.8 and the engine would stutter for a second or 2 when the engine cooling fan would fire up

 

[VE6SDG]

Glad to hear you got it figured out