strange occurance

[M1757]

2001 5.4 120,000mls. Driving 130 miles home today, got about 70mls in and battery gauge dropped down like engine was off, a/c and radio shut off and battery light and ABS light lit up. Everything came back after a few minutes then did it a few more times.

 

[bedrck46]

were you driving in the rain

 

[M1757]

No it wasn't raining while driving, it did rain over night last night though. I did replace my windshield last August also.

 

[M1757]

Everything was going out and coming back on so many times that it got to where when the a/c, stereo and windows went out I could detect a low click sound under dash on driver side and know everything was coming back in about 5sec.

 

[bedrck46]

could be a bad connection or the battery check for corrosion tightness of connections

clicking under the driver side of the dash could be any number of things Gem module but could also be a relay dropping out due to loss voltage (See above) or the relay going bad

Do you have the owners manual which would show the fuse block

 

[M1757]

Yes I have owners manual. I was just driving now with a/c on felt like it was going to stall when I took my got of gfs pedal. Battery gague also dipped some when I hit the window switch. I'm wondering if the voltage regulator or alternator is going.

 

[bedrck46]

possible have the alt and battery load tested again check all wiring on the battery for corrosion and tightness

how old is the alt and battery

how long have you had this problem

 

[M1757]

I bought the truck in June of last year, no idea how old battery or alternator is. Problem started yesterday coming home from a trip, drove about 70mls and it started. Stopped at a rest area and I shut the truck off thinking it may reset but it wouldn't start had to get a jump and it was fine but I didn't put the a/c back on either.

 

[bedrck46]

ok lets start by having the battery and alt tested and the wiring on the battery

 

[M1757]

Sounds good I'll start there.

 

[M1757]

Tested the alternator three times, it's perfect. The battery was pretty shot so I got a new one. Cables are all in good shape so guess I'll go over the truck real good and check every little thing.

 

[stamp11127]

Since you are in a salt environment during winter, corrosion is a big problem with electrical wiring if the salt water gets past the insulator. How do you know that your cables are in good shape - just on appearance or did you perform a voltage drop test?

 

[M1757]

I just visually inspected the cables.

 

[stamp11127]

This is one method I use to check wiring. You can't see the internal wire condition of a cable, so how do you know it isn't corroded inside? This test tells you. Max drop over the entire cable is .5v - From neg post to chassis and from pos post to starter, max is .5v drop (this is from our guidelines at my old job)

https://www.youtube.com/watch?v=3-9oZuX6-Pg

You use this procedure on any point in a harness. If you have a bad connection at the alt, this will tell you.
What is your charging voltage on the battery posts when engine is running? Use a dvm for this.

 

[M1757]

On the fuse block under the dash I found the number two relay with the prongs burnt and the plastic housing slightly cracked. It's labeled "battery saver relay". It was clicking every few minutes.

 

[bedrck46]

replace it clean all contact areas and use some dielectric grease on the contact area

 

[bedrck46]

will have to look into why it is clicking could be the bad contacts or possible other issues keep us posted and if I find any other information I will let you know

can you see if you can get the numbers of the prongs that were burnt they may be on the side or bottom of the relay

 

[M1757]

There are three portions in a row, the middle one was burnt. Another two prongs were in the opposite direction and the outer most one was burnt. The battery light cane back on for about 5sec then went out.

 

[stamp11127]

Usually there are markings on the bottom of the relay with the number next to the connector or a diagram on one side.
I would expect 30 & 87 to show the overload.

 

[M1757]

It's says on it PBT-GF20.