Does E40 ECM need to control cranking?
Does E40 ECM need to control cranking? I searched high and low for this but could not find it discussed before.
I am working on putting an LH6 from a 2005 Trail blazer with and E40 ECM into an old car. I modified the wiring harness and am using a fuse box from Current Performance (exceptional product by the way). The fuse box is setup for an LS1 conversion where the start/crank circuit is setup to take the crank signal from the ignition switch providing power to the relay. Studying the E40 wiring diagrams it looks like the E40 triggers the relay. It takes power input from the ignition switch on C1/53 then triggers the starter relay via a Ground signal on C1/13. For it to operate this way I would need to rewire the starter relay to be ground triggered instead of power triggered. Attached is the wiring diagram from the Trailblazer.
My question is does the E40 ECM need control the cranking? Or can I leave the starter relay as power triggered like it is done on the LS1?
I am working on putting an LH6 from a 2005 Trail blazer with and E40 ECM into an old car. I modified the wiring harness and am using a fuse box from Current Performance (exceptional product by the way). The fuse box is setup for an LS1 conversion where the start/crank circuit is setup to take the crank signal from the ignition switch providing power to the relay. Studying the E40 wiring diagrams it looks like the E40 triggers the relay. It takes power input from the ignition switch on C1/53 then triggers the starter relay via a Ground signal on C1/13. For it to operate this way I would need to rewire the starter relay to be ground triggered instead of power triggered. Attached is the wiring diagram from the Trailblazer.
My question is does the E40 ECM need control the cranking? Or can I leave the starter relay as power triggered like it is done on the LS1?
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I searched high and low for this but could not find it discussed before.
I am working on putting an LH6 from a 2005 Trail blazer with and E40 ECM into an old car. I modified the wiring harness and am using a fuse box from Current Performance (exceptional product by the way). The fuse box is setup for an LS1 conversion where the start/crank circuit is setup to take the crank signal from the ignition switch providing power to the relay. Studying the E40 wiring diagrams it looks like the E40 triggers the relay. It takes power input from the ignition switch on C1/53 then triggers the starter relay via a Ground signal on C1/13. For it to operate this way I would need to rewire the starter relay to be ground triggered instead of power triggered. Attached is the wiring diagram from the Trailblazer.
My question is does the E40 ECM need control the cranking? Or can I leave the starter relay as power triggered like it is done on the LS1?
I am working on putting an LH6 from a 2005 Trail blazer with and E40 ECM into an old car. I modified the wiring harness and am using a fuse box from Current Performance (exceptional product by the way). The fuse box is setup for an LS1 conversion where the start/crank circuit is setup to take the crank signal from the ignition switch providing power to the relay. Studying the E40 wiring diagrams it looks like the E40 triggers the relay. It takes power input from the ignition switch on C1/53 then triggers the starter relay via a Ground signal on C1/13. For it to operate this way I would need to rewire the starter relay to be ground triggered instead of power triggered. Attached is the wiring diagram from the Trailblazer.
My question is does the E40 ECM need control the cranking? Or can I leave the starter relay as power triggered like it is done on the LS1?
But it depends who tunes your ECM and what is in it from the factory. 
