My fresh rebuild has been a pain to start (only about 30 min run time). I went to crank it today, started loosing voltage slow cranking.

Throw the battery charger on medium charge like 30 amps. Go to crank it catches and is just about to start then BANG! I instantly let of the key it scared me, thought it was just a massive back fire. Then noticed the haltech went offline won't reconnect, key on, no fuel pump....****

Key off Key on, key off key on, nothing. Check fuses, good, relays seem fine.

I swap in another e6x (dead ign 1 driver, for the second time this year!!!) Other than the not firing leadings it works fine, but same issue, no pump, no connection. Mind you battery charger has been off since back fire, so no voltage spikes could have fried anything?? I feel like the problem must be in the harness but where? Have my 12v at pins 7 and 25, grounds fine, that should be enough to connect to my laptop correct?

But if that were the case then it should be enough to throw the relay for the fuel pump, which still has 12v going to it for the fuel pump feed.

Im confused, and I hate wiring, any info would be appreciated!

Matt

 

First, never use a battery charger while cranking the engine unless it is rated for high amperage (200+). The starter amp draw is massive. Some battery chargers, when they cannot supply the amperage draw, will allow straight 110 AC to pass through the charge cables. It's possible that you damaged the ECU by doing this.

Now that doesn't address the issue of the 2nd ECU. Do you have power to the ECU? Pins 7 and 25 should have constant power. The gray wire should have 12V+ when the key is in the ON and START positions. Do you have continuity to ground on pins 26 and 32?

 

Thanks for the input, I agree if something blew thats what did it, my charger is rated for higher amperage, I thought using the high settings 150+ was bad for it, not using the lower amp settings like I was, but what you said makes sense now that I think about it.

Anyways the e6x box is fine, (first one) After a few hours of pulling fuses, swapping boxes, checking relays and harness pins....I don't know, turned the key and everything was mint??? Engine fired right up, haltech connected first try?? I have absolutely no clue what happened, but I don't like it.

As far as the second ECU yes I'm using the same harness, and checked pins 7 and 25 today. Everything works on this ecu, powers up, connects, runs the car, just no leading spark. I had the same problem less than 1000 miles ago with this same ecu. Sent it to Haltech USA they confirmed dead ign1 driver, fixed and sent back. Worked fine for a very short period of time. Does anyone know why these would burn out? Something I'm doing wrong? Anyways I just swapped this one in to see if it would kick the pump on and connect to try to see if the other ECU was fried.

 

Unfortunately, the E6X has a propensity to lose ignition drivers.