[[Manual: Detailed.Output.Flyback.Config]]
The flyback is very important when inductive loads are driven (usually with low side drivers, such as p259 outputs or +4xNFETs).
- EC36-pin23 is the standard pin for flyback
- EC36-pin23 connected to the internal flyback rail with a - usually red - min 0.6mm2 airwire (standard for assembled controllers, do the same when you assemble yourself)
- EC36-pin23 must be connected to injector-common directly: no fuse between. The fuse is between injector-common and node15 (switched VBatt).
Tests before ECU powerup, retest after ANY change around the injectors or supply:
With ECM connected, but output load (injector) NOT, measure the flyback integrity with DVM at the injector connector.
- Low voltage flyback (eg. +4 NFETs) measures appr. 600..1500mV in DVM diode mode (when DVM- at the flyback=injector-common signal).
- High voltage flyback needs a current limited supply, such as 36V with a pullup resistor (eg. 2k7). In this case DVM is used in DC voltage mode, instead of diode mode.
Test flyback path integrity for every low-side output that will (or might ever) be connected.
- note: 2019-01-20 +4NFET product option was added to WebShop ** and all 4 related outputs have low voltage flyback diode common cathode connected to same EC36/23 node +tested, so if EC36/23 flyback is connected properly - as it should, anyway - then all 4 should be OK. However, with DVM diode mode (black probe to EC36/23 = injector shared+) it is still best practice, recommended and actually very quick ~1 min to test all NFET outputs (touch red probe to each, and verify DVM shows < 1.5V ).
With injector connected, but ECM not connected, measure at the ECM connector (EC36-wire) the existance of injectors: between flyback and injector- with DVM 200 Ohm mode (eg. if you measure 12.5 Ohm for highZ injector - 1 in an injector bank -, you know it's good ). Do this for every injector-banks. This test is less critical (for board safety) than the above, but very useful and worths to do.
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