What the ECR does
Your injectors and ignition coils need a switched 12V feed. Rather than running that straight off the ignition key, the Engine Control Relay (ECR) function lets the Nexus control the relay that supplies it. That means the ECU decides when the engine hardware gets power, not just the key.
If your car uses a Haltech universal wiring harness with the built-in fuse and relay box, keep this function enabled. The harness is designed around it, and turning it off can leave injectors and coils with no power at all.
The settings
- ECR Outputs: how many outputs follow the ECR state. Each one switches on and off together with the main relay.
- Enable Latched Output: the ECR turns on with the ignition input, but then stays on until a condition you set is met, even after the key goes off.
- Stop Condition: the rule that turns the ECR off when latching is in use.
Latching is useful when something needs to keep running after shutdown, such as a fan or pump that needs a few more seconds. Build the stop condition carefully so the relay always turns off eventually, otherwise it can drain the battery.
If a car cranks with no injector or spark activity, check that the ECR output is active in the software and that the relay is clicking before you chase anything else.
Replacement parts for the relay box include the 6 circuit Haltech fuse box. Related reading: Battery Voltage and Alternator Control.
