Shorted ignition

[i_taz]

Hi all, I shorted my choke lead and the car shut down....

What did I fry...???

 

[moparleo]

Depends on what wire you shorted to. Picture ??

 

[i_taz]

Dark blue, which runs to everything. I've banged it around before but this time
it landed right on a manifold bolt and sat there for a good second. I heard a little
discharge like a sizzle...

 

[moparleo]

That doesn't sound right. The choke wire should just be 12 volt source not connected to the ignition components.
Maybe you could get a shot that shows more than just the wire. Back away a little.
Time to get out the multi-meter and do some tracing.
Does anything electrical work ? Horns, starter ? Lights ?

 

[i_taz]

It was running and stopped dead in it's tracks. Now it cranks but won't fire. Lights ok...

The trouble shooting doesn't mention testing the ECU. I found a method on B bodies to grnd
each side of the dist pick-up lead coming from the ECU and look for a spark and I'm not getting it,
so my suspicions might be right after hearing that hiss AND the fact it's a MOPAR ecu....!
What's the deal with them, no re-pops ?

The coil lead goes to the alternator and comes back out and goes to the ballast.
So the short went thru the alt, ballast, volt reg and cooked the ecu ?

 

[70chall440]

Cooking the ECU is not an uncommon event for many, in fact even back in the day most carried a spare in the glove box. I was luck and never had much issue but I know some that went through them frequently. Alot of this has to do with connections, wire conditions, a good ground, etc. As connections age they build up corrosion which builds up heat and heat in the ECU's enemy. Also any errant grounds (on hot wires) aka shorts will kill them.

 

[i_taz]

You forgot, carelessness, I just hated to loose this one. Any recommendations ? I see some of the blue
ones are hi-rev U.S.A made... Rev a nator hasn't been available for some time... The MRE must be imported ?

 

[Challenger RTA]

Hoprfully it only blow the fuse-able link. that will shut it down like right now.

 

[moparleo]

The link I posted in posting #4 is on exactly how to troubleshoot this problem, what to check. Mopar ECU's are very common at most all part stores. Just not "performance" versions.
Here is one that is available:for MOPAR HR7500 Electronic Ignition Module Dodge Plymouth Chrysler MAX RELIABLE | eBay

 

[i_taz]

The link I posted in posting #4 is on exactly how to troubleshoot this problem, what to check. Mopar ECU's are very common at most all part stores. Just not "performance" versions.
Here is one that is available:for MOPAR HR7500 Electronic Ignition Module Dodge Plymouth Chrysler MAX RELIABLE | eBay

Yes it does thanks for that, I saved the file. I read down to were it said replace the ECU but wanted to
see if there was a way to check it separately. Turns out you do by grounding it, just not too much !

Over the years I heard how the orange boxes were unreliable and I felt fortunate
to have one in pristine condition. They still make the volt reg's but
can't have everything...

Are there other fusable links besides the starter...?

 

[halifaxhop]

No real way of checking them unless you have a tester. I have a bunch of ecu's on Fabo listed if needed, not the "new fake ones" All tested Hot and cold.

 

[i_taz]

Ya, It's all the same circuit so I really wasn't proving anything. I ordered one of the blue ones but PM'd you about any you may have I can use for shows. I'll miss the next to last show this weekend but
live and learn...

....just to clarify when I said the orange boxes were suspect i was referring to the aftermarket ones
not the factory...

 

[Challenger RTA]

There could be other fuse-able links depending on year and engine. missed that. there are 2 ignition circuits start and run. check for power at ballast resistor ignition on and check when cranking. no power check fire wall connections and steering column connections. choke power connects to ballast and ING side of voltage regulator and others. Alt 60 amps battery 1000 amps guess which one wins! Use a test light see were you loose power. I wouldn't condemn anything until I would find the problem. I have seen ecu's computers and a wast of time and money.because of lack of effort. Just fixed someones car,they were told it was the computer,igniter wiring harness,coil all different times.when everybody checked the fuses,checked out ok. By chance I was checking the wires and no power. pulled the fuse checked good.upside down. installed right side up no power. $1000.00 later and just a $5 fuse. go figure. seen this more than on time. Follow the power so money won't follow!

 

[i_taz]

Could you shrink it down..the top and bottom are cut off....thnx again !

 

[Challenger RTA]

What year and motor?

 

[i_taz]

"70 440...

 

[moparleo]

It will be in your Service Manual.

Service Manuals – MyMopar

mymopar.com

 

[Challenger RTA]

The years are pretty much the same with some differences. This is a good site. you can download manuals there.

Service Manuals, Parts Catalogs & How-To Guides

1970 to 1974 Plymouth Barracuda & Dodge Challenger Service Manuals, Accessories Catalogs, Service Training and Parts Catalogs. * = PDF FILES ARE VERY LARGE and may take a few minutes to download Service Manuals * 1970 Dodge Service Manual (Challenger) * 1970 Plymouth Service Manual (Barracuda) *...

www.e-bodies.org

 

[Challenger RTA]

Just to be clear.I think you understand 70 had no ECU it was incorporated. some 71 340s had an ECU.mine came factory dual point. Look at the 72 and up diagram for dual ballast and ECU wiring. This might make the ecu connections simplified. An other good link. https://www.e-bodies.org/Resources/Service_Manuals/1974_Barracuda_Challenger_Wiring_Diagram.pdf Not really go to the link.

 

[halifaxhop]

ECU started in 72 mostly a few late 340's had them in 71.