Static damage to dme

[nb6179505]

So...I had the brilliant idea of installing a SW chip I bought here on the forums this morning. Thought I read through the instructions well... Like most when I get in the garage it's tinkering and tinkering and logic is long gone

So I take out the dme from the car, mind you I started it up to center it in my two car garage beforehand. I use the first flat surface I find, the top of our dryer that has a towel on top

Long story short, put the dme back in the car, Icv not buzzing when ignition is on, for good measure replace it with a known good but old icv, still no buzzing

Smells like gas under the car, check the fuel pump, not leaking

Charge the car and crank, no spark. Replace the dme relay, still no power evident as icv still not buzzing

Is it possible that I fried the dme with static electricity? I did eventually get to installing the SW chip, car wouldn't start so replaced with stick chip, car still not starting

Read Bentley... But no spark. Contemplating these options

- buy a used dme for my 84 3.2
-reissue e my dme or buy and core charge, if so where do you guys recommend I send it
- take it to my local shop and have them deal with it

All information and insight much appreciated in advance

Noel


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[Flat6pac]

Wong, 911 chips can trade, diagnose, repair, or modify
Bruce

[walt]

And you are 100% certain you installed the chip in the correct orientation and it's fully seated. If it was installed 180 degrees out it may be ruined. Ask SW but I think they offer a service to test the unit.

[Lyle O]

Also be sure the large multi pin connector to the DME is properly seated (you’ve got to hear/feel the “click”). Check those pins for bends/connection individually.

[Bert87]

I do repair work on electronics (micro soldering), do not pay any mind to ESD, and have never damaged a device cause of it.

Either something is installed incorrectly or their was some type of physical damage done during the swap.

[Crude Rudy]

the DME relay is an analog relay not a silicon micro-IC, ESD will not damage it. Maybe an ASIC in the DME itself but I really doubt it. Computer digital components are at risk not auto electronics unless you have an open modern car ECU and are probing carelessly

[Quicksilver]

Originally Posted by Crude Rudy

the DME relay is an analog relay not a silicon micro-IC, ESD will not damage it. Maybe an ASIC in the DME itself but I really doubt it. Computer digital components are at risk not auto electronics unless you have an open modern car ECU and are probing carelessly

Who said anything about the relay?
The first line of his post clearly says he swapped the chip. A chip is in the DME. That is wholly electronic.

_________________________
Back to the OP.
The minimum static shock you can feel is in excess of 3000 volts. A shock you can feel could conceivably damage a chip but it is incredibly rare. As a rule professionals working on electronics don't worry much about static but they usually learn habits like resting their arm on the case and don't shuffle your feet.
But... Working on a towel on the drier is a bit of a 'poster child' for a high static work area. Automotive electronics are heavily designed to deal with rogue currents but with the case open it is possible to damage it but it is still unlikely.
I would (as mentioned before) check the pins on the wiring harness connector and be sure that it is fully snapped in place. It is possible that opening and moving the boards in the DME made a 'cracked solder joint(s)' issue in the DME to become critical.
If you have someone near that has an 84 thru 89 911 you can try plugging in your DME and see if the problem follows the DME. Otherwise it is going to be harder to chase this down without first getting the DME checked out.

[Porsche 935]

My Carrera had an aftermarket chip and I switched to Steve's. Was in upside down since no orientation available from original chip. Same gas smell. Rotated 180 and worked perfect. Try rotating it first.

[T77911S]

you said you put in an old but good DME and have the same symptoms.
come on now,

I would look at the connector to the DME as said above. look for bent pins.
make sure it goes on properly.


I also do electronics for a living. never had any ESD issues, never worn a grounding strap.

I kinda thought the same thing about working on a dryer.........

be a man, use the kitchen counter no matter how mad the wife gets.

as mentioned, are you certain you put the chip in in the correct orientation.

[nb6179505]

Connector for dme relay ended up having a frayed wire. Couldn't see, as it's under the seat, my independent found it, replaced the dme relay with a new oem...car is running again

Thanks for the responses. I was scared that ESD could void the electronics!

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[Quicksilver]

Originally Posted by T77911S

. . .
be a man, use the kitchen counter no matter how mad the wife gets.
. . .

^^ This ^^

[nb6179505]

We have a deal she doesn't touch my workspace I don't touch hers in the kitchen...

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[T77911S]

Originally Posted by Quicksilver

^^ This ^^

i have a bench in my garage specifically for electronics with Oscope, meters and some other stuff. I don't think I have worked on ANY thing electrical on it.
usually the kitchen counter

the bench has turned into a place to pile the stuff I don't know what to do with.

oh, I also have a hole in the rug from the soldering iron.

[RedCoupe]

Originally Posted by T77911S

i have a bench in my garage specifically for electronics with Oscope, meters and some other stuff. I don't think I have worked on ANY thing electrical on it.
usually the kitchen counter

the bench has turned into a place to pile the stuff I don't know what to do with.

oh, I also have a hole in the rug from the soldering iron.

Makes me feel good that I'm not the only one with this problem! 😄

[jpnovak]

Also look for cracked solder joints on the ignition driver FETs.

I too setup my electronic troubleshooting on the kitchen counter.

This happened recently to a local friend. Now its just a joint to touch up if the ECU is opened up.