Lighting Strikes

[Bill]

Disconnecting via ground or the positive isn't going to matter much. Voltage that high has the potential to jump any open circuits. Think of it this way. If lightning can jump the gap between a cloud and the ground, which can easily be several miles, it can easily jump the gap in a switch or relay.

 

[G8orFord]

Yeah, what he ^^ said. Lightning doesn't follow the rules all of the time.

 

[Bill]

Yeah, what he ^^ said. Lightning doesn't follow the rules all of the time.

Lightning follows all the rules. People don't understand the rules.

 

[Curious Hound]

Lightning follows all the rules. People don't understand the rules.

That is absolutely true.

Lightning around electronics is like a rampaging bull in a China shop. It just can't be gentle.

 

[85_Ranger4x4]

Lightning follows all the rules. People don't understand the rules.

+1

Even light pole stuff can jump a couple feet.

 

[G8orFord]

I figured someone would take my post too literally. I was right.

 

[adsm08]

So to update this, I have not found any burn marks, which rules out a direct strike, but not necessarily a spike by being too close to something else that got hit.

The instrument cluster started working once it's fuse was replaced, none of the other effected modules came back up, they all blew fuses again right away.

One thing I did notice, every fuse 10 amps or less was blown, none of the 15 and up fuses were blown.

Anyway, we priced out the worst case scenario, which was every component powered by every fuse that blows, since I could easily spend another whole day chasing them all individually, and the harnesses that connect to them. That list was $6000 just in parts.

 

[Uncle Gump]

I think the fact that it only popped the lower amperage circuits/components is a definite clue to what happened.

I'm not exactly sure where that clue would lead though. You sure would think a lighting strike would use no discretion on anything electrical.

 

[delaware74b]

adsm - check out ford tech makaluco's page on youtube. He worked on a first-gen escape that took a near strike. IIRC, it needed a cluster, fuel rail pressure sensor and an abs module.

 

[Snoranger]

I’m thinking they hooked up the jumper cables backward. We had a guy at work hook up 2 alternators backward.
One on a Cat loader... blew every fuse in the vehicle and burnt up a $12K module.
The other was an International 7400. Blew out 18 fuses, ECM, IDM, RPM, BCM, and the instrument cluster.
Never underestimate a simple reversal of power.

 

[adsm08]

I’m thinking they hooked up the jumper cables backward. We had a guy at work hook up 2 alternators backward.
One on a Cat loader... blew every fuse in the vehicle and burnt up a $12K module.
The other was an International 7400. Blew out 18 fuses, ECM, IDM, RPM, BCM, and the instrument cluster.
Never underestimate a simple reversal of power.

The only thing that makes me doubt a simple reversed polarity is that some of the effected circuit involve diodes. A 12V battery shouldn't be able to damage them.

 

[Uncle Gump]

The only thing that makes me doubt a simple reversed polarity is that some of the effected circuit involve diodes. A 12V battery shouldn't be able to damage them.

I know that most GM modules... at least the ones I worked with... protecting for this very scenario is outlined in the Component Technical Specs. and adhered to. I remember testing it on test bench mules for modules assigned to me. They are also protected for over voltage... can't remember the upper limits exactly. I'm sure Ford does the same thing.

 

[adsm08]

I know that most GM modules... at least the ones I worked with... protecting for this very scenario is outlined in the Component Technical Specs. and adhered to. I remember testing it on test bench mules for modules assigned to me. They are also protected for over voltage... can't remember the upper limits exactly. I'm sure Ford does the same thing.

Right. I know Ford does polarity protection. I don't have the specs on it.

 

[acsnowrider]

Is there any way to tell if a vehicle has been hit by lightning? Some visual cue that might not be obvious like blown out tires or melted wiring?

I'm working on one right now that has multiple modules that are shorted to ground internally, and at least one that is shorting the run and accessory pins of the ignition switch to power. It happened while the vehicle was left to sit unused for several months, and I can find no evidence of rodents, wiring damage, or the other usual suspects.

I'm just wondering if anyone knows of any more subtle visual cues I may be able to look for.

Incredible Head challenge, guy!!!! NEVER, ran across this one--Can tell you, that the "backward" hook up on the batt, AWAYS displayed arc damage, at the main terminals. Jump started everything from Airport ground support equipment to daily driver, and had gas power d/c gen sets that produced up to 36 d/c volts for Airport equip -35F jump starts (Cummins setups)--Heck, the jump start guy got my 66 Rambler running at -30F, with a 24 volt setup, and any damage from the hookup/high voltage, was always at the terminals.

 

[Ramcharger90]

@adsm08 i was messing around with a 91 BMW 535i today and basically every relay in the car but 3 of them were bad according to the tester. I thought maybe the tester was bad. So I pulled a bunch of new ones out of the box and tested those and they all worked. What could cause that mess?