Crank no start after accidentally touching both battery cables together while replacing the ECU?

2004 CHEVROLET AVALANCHE
3,749,220 MILES • 5.3L • V8 • 2WD • AUTOMATIC
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CAGUIRRETX
  • MEMBER
  • 1 POST
I replaced my ECU and had it programmed to my vin and the truck cranks but no start. It has a new fuel pump, new invitation ignition switch, new plugs, wires, and filter. I accidentally touched both battery cables together before I replaced ECU and since then no start.
Apr 26, 2024 at 5:10 PM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
  • ASE Certified Mechanic
Hi,

If the battery was disconnected and you touched the cables together, that won't hurt anything.

We need to determine if the engine is getting ignition spark and fuel. Chances are one or the other is missing. Also, pay attention to the anti-theft light. Does it stay on or blink?

Let me know that. On the other hand, try to see if it will start using starting fluid. If it does and then stalls, we know it is a fuel related issue. If there is no change, I need you to check for ignition spark at the plugs.

Here is a link that explains how to do it:

https://www.2carpros.com/articles/how-to-check-for-ignition-spark

Try this and let me know the results.

Take care,

Joe
Apr 26, 2024 at 8:38 PM
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