Before packing up your EMM, it's worth ruling out a few simple causes first - not every symptom means the module itself has failed. Here are the most common faults we see, and what to check.
Doesn't charge the battery
Check first: battery terminals for corrosion, the main charging fuse, and that the battery itself still holds a charge under load.
If those check out: the charging circuit inside the EMM is a likely cause and the module should be tested.
Won't switch on / no LEDs at all
Check first: the main power fuse, battery voltage at the engine harness connector, and that all harness connectors are fully seated.
If those check out: this usually points to a power-supply fault inside the module rather than the wiring.
Blown fuse when turning the key
Check first: replace the fuse once and try again - if it blows immediately every time, stop trying and don't keep replacing fuses.
If it blows again right away: there's a short somewhere in the circuit, commonly inside the EMM itself. Repeated blown fuses are a sign to send the module in rather than keep swapping fuses.
No 55V ignition regulation
What this means: the EMM isn't generating the high voltage the ignition coils need to fire properly, so the engine won't run correctly (or at all) even though it powers up.
Next step: this is a module-level fault that needs bench diagnostics - it's not something fixable from the outside.
Sensor circuit failure
Check first: the specific sensor's own connector and wiring for damage or corrosion, since a bad sensor is sometimes mistaken for a module fault.
If the sensor and wiring test fine: the fault is in the EMM's sensor input circuit.
Still seeing the issue after checking the basics?
Start a Repair Request