Discussion and questions related to the course Practical Harness Construction - Club Level
I have a 2012 Cruze that has an unused, fused pin in the fuse box that is powered by the main ignition relay. I haven't been able to find data to tell me exactly what size the relay is, it's GM part number 13306941. I attached the wiring diagrams that I have for the relay. The unused pin that is available is X3-4. The devices I need to connect are the following:
1. AEM water/meth controller - connects directly to battery, has its own fuse, has switched ignition lead that I assume is just to arm it, but should draw its current from the battery?
2. water/meth solenoid with 0.75A current
3. back-up camera with 60mA current
4. E85 sensor - Continental (GM) 13577394, and I can't find any amperage data on it.
The schematics show the unused pin with a 7.5A fuse. Would I be safe connecting all those devices to the unused pin of the main ignition relay, or would it be better to power a separate relay from that pin and give the devices their own fuse? Except for the water/meth controller, it has its own fuse.
I doubt you'll have any issue using the output from the factory relay given what you want to drive. I don't have specifics on the continental sensor however I'd suspect they current draw is very low given that I'll usually wire these with 20 or 22 AGW wire. Most sensors are typically below 1 amp current draw as a general rule and nothing else you've listed is of significant concern - You're right that the WMI system will draw its current direct from the battery via its own separate fuse.
Awesome, thanks Andre!