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Topic: Open ground **SOLVED** (Read 785 times) previous topic - next topic

Open ground **SOLVED**

Ive been wanting to post this for a long while,,, but every time someone says make sure your battery cables are tight, i typically think,, yeah yeah, Like we dont already know this.

after my "dont forget to pull the pin on the granade" alternator issue with my oldest son "mason", the following happened:

I get back in town from a road trip and ......

mason says- Dad, my bird wont start
me- ok, lets work it out tomorrow, its 2am now
(while i was gone, mason deleted his electric fan setup for the original stock fan clutch,,yes there were many wires, relays and made me wonder what could be the problem because it would not start after he took all this out)

tomorrow comes, hood up , tools ready, me at the battery ,mason inside the car

me- ok mason, turn the key forward
mason- ok

we hear nothing, no fuel pump

me- turn on the headlamps, nothing
me- open the door, no dome lights
me- turn on the radio, nothing
me- hit the  horn,  nothing
me- WTF!!!!!!!!!

mason- whats wrong dad?
me- nothing, get me a timer!!
 (we call our beers "timers" because it helps me time when i flip food on the grill, one beer = one complete set of thick burgers:D )

me- well now
mason- yeah
me- what the hell did you do to this thing
mason- nothing dad, i did exactly what you suggested, i just went back to the original setup and put everything just like stock.  It was easy.

me- well you did something cause we have no power anywhere
me- did you read the battery
mason- yep, about 12 and a half volts across the battery

me- humm
I get the meter and there is before me what apparently is a fully charged battery *measuring from POST to POST*.
I measure from the positive post to the frame of the car and get flickering voltage and see a level of 12v showing up and going away.

Me- WTF!!!!
mason- what dad?
me- nothing
mason- dad, thats not normal, i think you found the problem.
me- well,, not yet

I measure voltage from the positive battery post to the engine bay- nothing
I measure continuity from the negative battery post to the car chassis -nothing

me- wtf!!
mason- nothing but crickets from mason at this point
mason- man i hope i didnt kill the bird
me-  i dont smell burnt shiznit and so far i cant see why anything is dead, lets press on.

I measure continuity from the neg battery cable connector to the bond at the engine bay- BAM!!!  continuity found!!!

I measure continuity from the negative battery post to the engine block-  BAM!! OPEN

I measure continuity from the negative battery "connector" to chassis ground and my meter alerts me there is voltage.  I do indeed find 12v from the negative cable connector directly to chassis ground.

I measure voltage from the positive cable to the negative cable and get flickering voltage of 12 or so volts in and out like its flickering.

AND FINALLY!!!!!!!!!
I measure for continuity from the negative battery post to the negative battery cable connector - ****OPEN****

Mason- opps,
me- yep, i told you that there is a reason why battery cable connectors and posts are tapered.  Now loosen the connector hardware, spread out the connector , ***THEN put it on*** and tighten.

as soon as mason started undoing the connector on the negative post, things started cutting on and off and we knew this was solved.

I told mason this will likely be the last time he ever see's an open ground electrical example in a car so enjoy it and remember the symptoms.

anytime you have source power from chassis ground to a ground wire, you have an open.