Yamaha F115, F130 and F150 Diagnostics by App: From Cable Control to Digital Shift

Few classes are as common as the four-cylinders between 115 and 150 hp, and few have gone through as many ECU versions. An older F115 on mechanical cables and a new F150 with digital shift have little in common in their fault memory. M-JET DIAGNOSTIC identifies the ECU at the diagnostic connector and shows on your phone, over Bluetooth, exactly the values and tests that particular engine supports.

Models covered

F115A, F115B and F115C, F125A, F130A, and the F150 in versions A/D, B/F, C, G, H, J, L and P. Most also exist as counter-rotating FL models, which the app handles the same way. That adds up to twelve ECU variants. Depending on the variant, the ECU delivers 19 to 55 live values, knows 10 to 76 fault types and offers 6 to 11 actuator tests. Idle learning is available on all twelve. What counts is the ECU generation, meaning the year the platform was introduced, not the build year of your engine.

What newer ECU generations add

• Electronic throttle valve (ETV) with two throttle position sensors, TPS1 and TPS2, and an ETV relay
• Accelerator position sensors APS1 and APS2 at the remote lever instead of a throttle cable
• Digital remote shift with shift position sensors SPS1 and SPS2, shift request in percent, neutral detection and start permission
• Engine temperature and oil pressure in kPa as live readings, plus the thermo switch
• on some ECUs variable cam timing with intake cam angle and the OCV, the oil control valve
• Trim sensor, trim switches and relays, immobilizer status

Baseline values every engine in the class shows

Engine rpm, intake air pressure, atmospheric pressure, ignition timing, battery voltage, throttle valve angle, injection duration and intake air temperature form the base. Depending on the ECU, TPS voltage, the ISC valve and cooling water temperature are added. Some engines add cooling water pressure, fuel flow and boat speed. For troubleshooting that's usually plenty: watch intake air pressure and throttle angle at idle and you'll spot an air leak or a sticking throttle plate faster than with a screwdriver.

Actuator tests from fuel pump to OCV

Depending on the ECU you can run the electric fuel pump, the low-pressure pump, the ISC valve and the OCV. Ignition coils and injectors go either one at a time for cylinders 1 through 4, or in pairs, 1 and 4, then 2 and 3. The single-cylinder test is worth a lot when a cylinder drops out, because you can check coil and injector separately without swapping plugs.

Faults that show up a lot in this class

Besides the usual suspects like the thermo sensor, pulser coil, knock sensor, battery voltage and water in the fuel filter, this class knows faults on the oil pressure sensor, the shift cut-off switch, the thermo switch, the cam position sensor and the OCV. With ETV and digital shift you get a long list of entries for ETV, TPS, APS and SPS, plus communication errors between engine and remote control and irregular signals from the lever sensors inside the remote. A trim sensor out of range or a failed trim buzzer also end up in memory. What none of these entries reveal: a worn impeller, carboned valves, a spun prop hub. That's still hands-on work.

Related topics

• Yamaha Outboard Electronic Throttle (ETV): Checking TPS and APS
• Yamaha Outboard Live Engine Data on Your Phone
• Yamaha F175, F200, F225 and F250 Diagnostics: Inline Four and V6 by App
• All Yamaha outboard diagnostics topics

Everything runs via app over Bluetooth, for Yamaha outboards with control unit generations from 2003. Learn more about the M-JET DIAGNOSTIC for Yamaha WaveRunner & Outboard.