I’ve been working on diagnosing an electrical issue in a 2014 Genesis Coupe and have run some tests on the ECM harness based on some guidance I received. Using a multimeter, I took readings at various points with the ignition in the “on” position. The ground points (#5, 6, 30, 55, 80) all measured around 5.2 Ohms.
Moving to other points, I found the following readings:
- #52 Battery: 12.26 volts
- #75 ECR Relay “on” input: 0.87 volts
- #77 Battery: 12.26 volts
- #94 ECR control: 12.25 volts
- #99 ECR “on” input: 0.87 volts
- #100 ECR “on” input: 0.87 volts
It seems the ECR main relay is only transferring a very low voltage, around 0.87 volts, to its “on” inputs when it’s energized. This seems like a potential problem area in the system.
To further investigate, I tried testing the ECR and fuel pump relay following some instructions. The guide mentioned that if there’s a problem with the ECR, it should be replaced with a known good fuel pump relay for testing purposes. I tested both relays, but unlike the ECR, the fuel pump relay doesn’t have a schematic diagram on it to easily identify pins.
For the ECR, testing the control pins (85 & 86) showed a resistance of 16.2 ohms, while the load pins (87a and 30) showed infinite resistance. Even with the ignition off, there’s constant voltage at pins 86 and 30 of the ECR.
The fuel pump relay (FPR) control pins (the darker bronze pins in the image) measured 88 ohms, and the load pins (lighter gold colored pins) also showed infinite resistance. The only pin on the FPR with constant voltage when the ignition is off is the bronze pin furthest to the right.
Finally, and importantly, I was unable to find a ground on the ECR connection at the fuse box, regardless of whether the ignition was on or off. This lack of ground could certainly be contributing to the issues I’m seeing.
Could the low voltage reading at the ECR “on” inputs and the absence of a ground be related problems? Is there a possibility that using an OBD2 scan tool, such as a BlueDriver, could provide more insight into these electrical issues in my 2014 Genesis Coupe? Any guidance on how to proceed with diagnosing this further would be greatly appreciated.
