lights flickering after HO install

[Ali1 10+ year member]

So i installed my 270 amp alternator, but i found out that my headlights,dashboard lights, and my interior lights are flickering really fast. I have no sound system yet. Just the HO alt and a redtop battery underneath. Voltage is showing a strong 14.7v. I noticed this yesterday night when I was driving and seen the reflection of my headlights on the ground. Then i looked in my dash and my interior lights and they are doing the same thing.

Anyway to fix this?

Pictures Attached...

Click to read more...

 

[Ali1 10+ year member]

ttttt

 

[HvNd4Speed 10+ year member]

what kind of vehicle is it?

 

[Ali1 10+ year member]

2004 blazer

 

[basscort2009 5,000+ posts]

in for the answer, my HO alt does that too. check the voltage. mines real inconsistant. i think my regulator or some part of the alternator is not right

 

[Ali1 10+ year member]

What do you mean by inconsistant? Whats the range ?

Mines is showing a strong 14.7v.

Big3 has been done

 

[basscort2009 5,000+ posts]

mines a little jumpy

 

[Ali1 10+ year member]

mines a little jumpy

Jumping at what levels though

 

[basscort2009 5,000+ posts]

like 15.4 to 13.9 sometimes

 

[Ali1 10+ year member]

Interesting and what company is this?

 

[HvNd4Speed 10+ year member]

i wish i would have put money on the answer to that....i had a 98 blazer...same issue.....i never got to the bottom of my problem and ended up selling the truck anyway...

i was running a ppi a600.2 to 3 10w6's and my output from subs would fluctuate...at low rpm's...it was like the amp wasnt making enough power...on highway...it would come and go....at some points...the bass would be really full sounding and then drop off and sound flat....i was only running about 1K watts total...i had a capacitor....

only thing i did notice was when my battery failed and i replaced it.....the flickering of light stopped for about a week and then came back....i was gonna say try doing the big 3 but looks like you already have....I even replaced the stock alternator from a newer model salvaged gmc jimmy i had and it did the same thing...BUT...that alternator in the jimmy when i got it running....no light flicker....definitely a weird issue and is common to the blazer line....good luck with it!

 

[Ali1 10+ year member]

so your telling me i'm fvcked....

 

[Ali1 10+ year member]

Does the ext voltage regulator have to be mounted on the chassis? Can it just be tossed in the back of the SUV laying on carpet?

 

[bubbagumper6 5,000+ posts]

What do you mean by inconsistant? Whats the range ?

Mines is showing a strong 14.7v.

Big3 has been done

Not necessarily, if it's pulsing fast enough your DMM might not be able to detect the fluctuations...you'd need an O-scope to see it.

 

[nateberrier 10+ year member]

Sounds like the voltage regulator on the alt