Most Suzuki outboards with electric start use a 30 A main fuse; larger EFI motors add separate fuses for the starter relay, the ignition/injector/ECM circuit, the fuel pump, the PTT switch and, from the DF100A/115A/140A family up, a fuse inside the sub-battery cable. Ratings, circuits and locations are listed below by family, straight from the owner's and service manuals. Every manual says the same two things: replace a blown fuse only with one of the same type and rating, and if it blows again, find the cause instead of fitting another fuse.
If the starter does not turn, the manuals list a blown fuse as one of the first three causes on every electric-start model. Check the lanyard plate and neutral first, then the fuse.
Suzuki outboard fuse chart by family
Ratings are as printed in the manual named in the first column. Where a manual we have does not print the fuse box listing, the row says so; check the label on your fuse box cover.
| Family (manual used) | Fuses: rating and circuit | Where it is | Spares and notes |
|---|---|---|---|
| DF2.5, DF4A/DF6A (manual start) | No fuse listed in the owner's manuals we have (no battery on these models) | — | — |
| DF8A/DF9.9A electric start (2014 owner's manual; service manual 99500-99J00) | 20 A, electric start model (service manual). The owner's manual gives no rating, only "same type and rating". | Under the motor cover, in a fuse case with a cover | Not stated |
| DF9.9B/DF15A/DF20A electric start (2014 and 2020 owner's manuals; service manual 99500-89L00) | Main 30 A (white fuse case); ECM 10 A (yellow fuse case) | Under the motor cover, in fuse cases with covers | Not stated. Service manual notes: a blown PT-system fuse is the first cause listed when a power-tilt model will not tilt at all; the manual-start model's optional battery-charging circuit is drawn with a 20 A fuse. |
| DF25A/DF30A (2019 owner's manual; service manual 99500-94L10) | Main 30 A (white fuse case), all electric-start models; ECM 10 A (yellow fuse case), DF25AT/25AR/30AT (service manual: remote control model) | White (main) and yellow (ECM) fuse cases | Not stated |
| DF40A/DF50A/DF60A (2022 owner's manual; DF60 service manual 99500-88L01) | Main 30 A; PTT switch 15 A; Ignition coil/Injector/ECM/IAC 30 A; Starter motor relay 30 A; Fuel pump 15 A | Fuse box under the motor cover; key off first, then remove the fuse box cover | Spare 30 A in the box (position 5); spare 30 A and 15 A on the back of the fuse box cover; fuse puller on the back of the cover |
| DF75/DF90A (2023 owner's manual); DF70A/DF80A/DF100B (service manual 99500-87L10, same ratings) | Main 40 A; PTT switch 10 A; Ignition coil/Injector/ECM/Fuel pump 30 A; Starter motor relay 30 A; IAC 10 A | Fuse box on the electric parts holder; the ECM main relay is in the same box | Spare 40 A, 30 A and 10 A; spares 7 and 8 are on the back of the fuse box cover |
| DF100A/DF115A/DF140A (2016 owner's manual; service manual 99500-92J00) | Main 60 A; Load 60 A; Starter motor relay 30 A; PTT switch 15 A; Ignition coil/Injector/ECM/IAC 30 A; Fuel pump 15 A (owner's manual; the service manual prints the same ratings); plus a 15 A fuse in the sub-battery cable | Fuse box under the motor cover: key off (or Keyless Start System off), remove the motor cover, then the fuse box cover (owner's manual); the service manual places the box in the electric part holder behind the PORT lower side cover; sub-battery fuse in the middle of the sub-battery cable | Spares 30 A, 15 A and 60 A in the box (positions 3, 4 and 9); fuse puller on the back of the fuse box cover |
| DF115B/DF140B (2023 owner's manual) and DF115BG/DF140BG (2022–2023 owner's manual) | DF115BG/140BG: Starter motor relay 30 A; Ignition coil/Injector/ECM 30 A; Throttle valve 15 A; Shift actuator 15 A; PTT switch 10 A; Fuel pump 15 A; Load 60 A; Main 60 A; Sub-battery cable fuse 30 A. DF115B/140B: 15 A fuse in the sub-battery cable; that manual copy does not print the fuse box listing, so check the label on your fuse box cover. | Fuse box under the motor cover (DF115BG/140BG: remove the motor cover, then the fuse box cover); sub-battery fuse in the middle of the sub-battery cable | DF115BG/140BG: spares 60 A, 30 A, 15 A, 10 A and 30 A; the 30 A, 15 A and 10 A spares are on the back of the fuse box cover, with the fuse puller. DF115B/140B: not stated |
| DF150A/DF175A/DF200A (2020 and 2023 owner's manuals) | Starter motor relay 30 A; Ignition coil/Injector/ECM/Fuel pump 30 A; PTT switch 10 A; Main 60 A; Isolator select 30 A (STD and OPT positions); IAC/VSV/VVT 10 A; Sub-battery cable fuse 15 A (2023 manual; the 2020 manual prints the same 15 A sub-battery fuse and 30 A isolator fuse) | Fuse box under the motor cover; sub-battery fuse in the middle of the cable | Spares 60 A, 30 A, 10 A and 15 A; the 30 A and 10 A spares are on the back of the fuse box cover; fuse puller on the back of the fuse box cover |
| DF150AP/DF175AP/DF200AP (2020 owner's manual) | Starter motor relay 30 A; Ignition coil/Injector/ECM/Fuel pump 30 A; Throttle valve 15 A; Shift actuator 15 A; PTT switch 10 A; Main 60 A; Isolator select 30 A; Sub-battery cable fuse 30 A | Fuse box; sub-battery fuse in the middle of the sub-battery cable | Spares 60 A, 30 A, 15 A, 10 A and 30 A; fuse puller on the back of the fuse box cover |
| DF225/DF250 (2022 owner's manual) | Main 60 A; Sub fuse 30 A; 15 A fuse in the sub-battery cable | Fuse case under the electric parts holder cover (under the motor cover); sub-battery fuse in the middle of the cable | Not stated |
| DF250AP/DF300AP (2022 owner's manual) | Starter motor relay 30 A; Ignition coil/Injector/ECM/High-pressure fuel pump 30 A; Throttle valve 15 A; Shift actuator 15 A; PTT switch 10 A; Low-pressure fuel pump 15 A; Main 60 A; Isolator select 40 A; Sub-battery cable fuse 30 A | Fuse box under the motor cover; sub-battery fuse in the middle of the cable | Spares 60 A, 30 A, 15 A, 10 A and 30 A; the 30 A, 15 A and 10 A spares are on the back of the fuse box cover, with the fuse puller |
| DF300B/DF350A (2023 owner's manual; set-up manual 99505-98L40) | Starter motor relay 30 A; Ignition coil/Injector/ECM/High-pressure fuel pump 30 A; Throttle valve 15 A; Shift actuator 15 A; PTT switch 10 A; Low-pressure fuel pump 15 A; Main 60 A; Isolator select 40 A (STD/OPT); Sub-battery cable fuse 30 A | Fuse box under the motor cover (remove the motor cover, then the fuse box cover); sub-battery fuse in the middle of the sub-battery cable | Spares 60 A, 30 A, 15 A, 10 A and 30 A; the 30 A, 15 A and 10 A spares are on the back of the fuse box cover, with the fuse puller |
The sub-battery cable fuse and the isolator fuse
From the DF100A/115A/140A up, the engine control system is fed by a second, thinner cable from the battery: the sub-battery cable. Its fuse sits in the middle of the cable, not in the fuse box, and the manuals say plainly that if the sub-battery cable is not correctly connected the engine cannot be started. On the DF115BG/140BG, DF150AP/175AP/200AP, DF250AP/300AP and DF300B/350A the sub-battery cable fuse is 30 A; on the DF100A/115A/140A, DF115B/140B (2023 DF115B/DF115BS/DF140B manual), DF150A/175A/200A and DF225/250 it is 15 A. Suzuki's set-up manuals tell the installer to put this fuse somewhere the operator can see it. If the motor is dead with a good battery, this is the fuse to find.
Two groups work the other way round. The DF70A/80A/90A/100B set-up manual says it is not necessary to connect a sub-battery cable to power the engine control system on that model, and that if you connect one, the sub-battery fuse will blow. The DF9.9B/15A/20A (T models) and DF25A/30A set-up manuals carry the same kind of notice: do not connect the sub-battery cable to the remote-control harness, or it blows the sub-battery fuse.
The isolator fuse is different again. It has two positions, STD and OPT, and only does something in OPT. The DF150A/175A/200A and DF150AP/175AP/200AP owner's manuals say to check the 30 A fuse in the OPT position if a second accessory battery is not charging; the DF250AP/300AP manual says the same about a 40 A fuse, and the DF250AP/300AP and DF300B/350A manuals note that moving the 40 A fuse from standard to option with the optional battery isolator lead assembly installed is what enables dual-battery charging. Full details are in the battery cable and wiring guide.
Symptoms of a blown fuse
- Starter motor will not operate. Every electric-start owner's manual lists "fuse is blown out" alongside "shift lever is not in NEUTRAL" and "emergency stop switch lock plate is not in position". The DF150AP/175AP/200AP and DF250AP/300AP manuals split it into "starter relay fuse is blown out" and "sub battery cable fuse is blown out".
- Motor will not trim or tilt at all. The DF9.9B/15A/20A and DF70A/80A/90A/100B service manuals list a blown fuse for the PTT (PT) system as the first cause to check; on the DF70A family the manual names the main 40 A, PTT switch 10 A and ECM 30 A fuses.
- Battery not charging. The DF70A/80A/90A/100B service manual lists "main fuse blown out" among the causes when the alternator does not charge. A second battery not charging points to the isolator fuse described above.
Before chasing wiring, the service manual for the DF9.9B/15A/20A has a four-item pre-check for the electric starter system: battery fully charged, all cables and wires securely connected, shift in neutral, fuse not blown. A run-down or badly connected battery can also trigger the low battery voltage caution on motors that have one, which is not a fuse problem.
How to check and replace a fuse
- Turn the ignition key to the off position (on the DF8A/9.9A this step is listed for the remote-control model).
- Remove the motor cover. On the DF225/250, also remove the electric parts holder cover.
- Remove the fuse box (or fuse case) cover and pull off the fuse. The DF40A/50A/60A, DF100A/115A/140A, DF115BG/140BG, DF150A/175A/200A, DF150AP/175AP/200AP, DF250AP/300AP and DF300B/350A manuals say to use the fuse puller on the back of the fuse box cover when pulling and fitting fuses.
- Inspect the fuse. The DF9.9B/15A/20A service manual's test is continuity across both terminals of the fuse: no continuity, replace the fuse. The owner's manuals show a normal and a blown fuse element side by side.
- Replace with a fuse of the same type and rating.
- On motors with a sub-battery cable, remember that its fuse is in the cable, not the box.
If it blows again
The DF25A/30A, DF40A/50A/60A, DF150AP/175AP/200AP and DF225/250 manuals all carry the same notice: if a fuse is blown, try to determine the root cause and correct it; if the cause is not corrected, the fuse may blow again. The DF75/90A manual goes further: if a new fuse blows a short time after installation, you may have a major electrical system problem. That is the point to stop and have an authorized Suzuki marine dealer test the circuit. If the motor is under warranty, check with your dealer before opening harnesses. If the motor is also flashing a check-engine code, see the diagnostic codes page.
Parts for this job
Blade fuses, fuse cases, spare fuse holders and pullers are in our Suzuki OEM fuses, bulbs and electrical accessories collection. Starter relays, main relays and rectifier/regulators are under starters and charging systems, and sub-battery cables and harnesses under wiring harnesses and cables. If you are sizing a new battery or cable run, see the battery requirements chart. Free shipping on orders over $149 to the lower 48.
Sources: Suzuki owner's manuals for DF8A/9.9A (2014), DF9.9B/15A/20A (2014 and 2020), DF25A/30A (2019), DF40A/50A/60A (2022), DF75/DF90A (2023), DF100A/115A/140A (2016, 99011-90J70-03B), DF115B/140B (2023) and DF115BG/140BG (2022–2023, 99011-99L20-03B), DF150A/175A/200A (2020; 2023, 99011-96LM0-03B), DF150AP/175AP/200AP (2020), DF225/250 (2022), DF250AP/300AP (2022), DF300B/350A (2023, 99011-98L60-03B); Suzuki service manuals 99500-99J00, 99500-89L00-01E, 99500-94L10-01E, 99500-88L01-01E, 99500-87L10-01E, 99500-92J00-01E; Suzuki set-up manuals 99505-87L50-01E, 99505-92J20-01E, 99505-98L40-01E and the DF9.9B/15A/20A and DF25A/30A set-up manuals. Figures are Suzuki's published values; confirm against the manual for your model year and serial number.