Electrical Refresh

1. Park the trailer level. Chock both rear wheels. If hitched to the truck for the jack swap (Phase 02), leave it hitched; otherwise unhitch and pull the truck away.
2. Unplug shore power if connected. Do this BEFORE you touch the battery cables. Disconnecting the battery alone does NOT kill 12V if the PD9140A converter is being fed by shore power.
3. Open the V-nose front compartment and locate the existing Super Start battery in its battery box.
4. Photograph the battery wiring before you disturb it. Document each fuse branch on the positive terminal: the heavy 6 GA cable to the converter, and each inline ATC fuse (note the amp rating and the wire color it feeds). Wide shot showing the whole layout, then close-ups of each fuse holder.
5. Label every wire entering and leaving the battery area with masking tape and Sharpie. Note its destination if you can trace it. This is your reassembly map for landing each branch on the new busbar.
6. Disconnect the existing battery: negative cable first (the black one), then positive (the red one). Tuck each cable end somewhere it can't touch metal.
7. Verify the trailer is dead. Try the interior lights. They should be off. If anything is still powered, the converter is probably still being fed by shore power, recheck step 2; or you have a wire bypassing the battery somewhere, stop and trace it before continuing.

8. Locate the existing Cesco junction box on the tongue and find the breakaway switch and battery inside. You're not touching this yet, just being aware.
9. Confirm the trailer is hitched to the F-250 with the coupler latched and safety chains crossed, and the 7-pin is disconnected. The truck supports the tongue weight; no jack stand required since the seized old jack isn't doing any holding work either.
   Stay clear of the shear zone (under the tongue) while it's only supported by the hitch coupler. If anything ever lets go, that tongue drops fast.
10. Unbolt the 3 bolts at the triangular jack flange. The old jack should come right out. Set it aside.

11. Chase the rusty tapped threads clean. The factory plate is tapped (threaded), so the new bolts thread directly into it. Rust in the threads adds false friction and you'll hit your torque target before the bolt is actually tight. Squirt WD-40 Specialist Degreaser (NOT regular WD-40 or grease, both leave a lubricant film that throws torque off) into each hole, run the supplied bolt in and out by hand a few times, wipe out the crud. Repeat until the bolt spins smooth.
12. Position the Polestar over the 3 tapped holes. Bolt pattern matches (verified earlier).
13. Insert the 3 supplied bolts, each with a flat washer under the head (stack: bolt head → washer → jack flange → plate). Hand-tight only. The plate is tapped, so the bolt threads INTO it; no nut on the back side. Make sure the jack is vertically aligned and the motor housing faces a convenient direction (road-side is usual).
14. Optional but recommended: blue Loctite (242/243) on the cleaned threads before final torque. Without lock nuts on the back, vibration is what backs these out. Loctite is the simple insurance; the factory accepted you'd re-check periodically instead. If you skip Loctite, add "re-torque jack bolts" to your post-first-trip checklist.
15. Torque to spec. Measure your bolt diameter if unsure: 3/8" Grade 5 wants ~30 ft-lb, 1/2" wants ~75 ft-lb. The new jack's manual is authoritative if it lists a spec. Don't over-torque or you'll strip the tapped plate threads.

flowchart LR
  OLD["Existing cable
(ring terminal already crimped,
stacked on a stud-post adapter)"]
  CHECK["Verify ring inner diameter
matches AGM stud
(M8 = 5/16″, M10 = 3/8″)"]
  FITS{{Ring fits?}}
  READY["Ready to bolt onto
AGM stud directly
(no re-termination)"]
  SWAP["Cut ring off, crimp new
5/16″ or 3/8″ ring,
heat shrink"]
  OLD --> CHECK --> FITS
  FITS -- yes --> READY
  FITS -- no --> SWAP --> READY
      

16. Remove the old Super Start battery from its loose plastic box. ~40 lbs, lift with your legs.
17. Remove the old loose box entirely. Wire-brush the V-nose floor underneath, clear any rust or debris.
18. Position the new Attwood 9084-1 where you want it. Cable exit ports face the disconnect/wiring side. If using a rubber anti-fatigue pad underneath, place it now and set the box on top.
19. Mark the 4 mounting hole locations with a pencil through the box's base flange holes. Lift the box off, drill 1/8" pilot holes at the 4 marks.
20. Drive 4 stainless #10 x 1.25" wood screws through the flange holes into the V-nose floor. Snug but don't strip. Verify the box doesn't shift under firm hand pressure from any direction.
21. Set the new Renogy 100Ah AGM into the secured box. Should sit flat with about 1/4" clearance on each side.
22. Verify the existing cables are stud-ready. The old setup uses a tapered-post adapter (copper clamp around the post with a vertical 5/16" or so stud on top); multiple cables are already terminated with heat-shrink ring terminals and stacked on that stud under one nut. The cables themselves are ready to bolt directly onto the new AGM's threaded studs — no re-termination needed. Check that each ring terminal's inner diameter matches the AGM's stud size (M8 = 5/16", M10 = 3/8"). If a ring is too small to slip over the AGM stud, cut it off and crimp a new one in the matching size; if it's too big (e.g., 3/8" on an M8 stud), it will still bolt down but the fit is sloppy.
23. Skip the NCP2 felt washers on this battery. They're designed for tapered posts and don't fit on threaded studs. A small dab of dielectric grease at each stud connection during final assembly seals against moisture.
24. Don't connect cables to the battery yet. Next phase installs the disconnect switch; cables get bolted to the AGM studs after the disconnect and busbars are wired. Note: the existing stack of multiple cables on one stud will be split apart in Phase 06 — only the disconnect feed stays on the battery, everything else moves to the busbar.

flowchart LR
  BATTP["Battery (+)
stud"]
  DIN["Disconnect
INPUT stud"]
  DSWITCH{{Blue Sea 6005}}
  DOUT["Disconnect
OUTPUT stud"]
  PEND[/"+ Busbar
(wired in Phase 06)"/]
  BATTN["Battery (−)
stud"]
  BATTN_DIRECT["(negative cable
direct to battery − stud,
no disconnect on neg)"]
  BATTP -- "6 AWG / 3/8″ ring" --> DIN
  DIN --- DSWITCH
  DSWITCH --- DOUT
  DOUT -. open until Phase 06 .-> PEND
  BATTN --- BATTN_DIRECT
  classDef existing stroke:#a8a29e,stroke-width:1.5px,color:#a8a29e
  classDef new stroke:#ff8c42,stroke-width:3px
  classDef pending stroke-dasharray:5 3,stroke:#a8a29e,color:#a8a29e
  class BATTP,BATTN,BATTN_DIRECT existing
  class DIN,DSWITCH,DOUT new
  class PEND pending
  linkStyle 0,1,2 stroke:#ff8c42,stroke-width:2.5px
  linkStyle 3 stroke:#a8a29e,stroke-dasharray:5 3
  linkStyle 4 stroke:#a8a29e,stroke-width:1.5px
      

25. Find a mounting location for the switch within easy reach of the battery. Common locations: wall next to the battery box, mounting bracket on the box, panel near the breaker panel.
26. Mount the switch using 4 screws into wood or sheet metal. Make sure you can reach the knob without fishing into a tight space (you'll flip it every storage cycle).
27. Connect the battery positive cable to the input stud of the disconnect switch. The cable should already have a ring terminal crimped on (Phase 04). If not, do that now. Heat shrink until adhesive flows.
28. Connect the battery negative cable directly to the battery negative stud (bolt the ring terminal onto the AGM's threaded stud, washer + lock washer per the battery's hardware). The disconnect only goes on the positive side.

29. Flip switch back to OFF before continuing.

Replaces the stacked-wire mess on the battery terminals with clean distribution downstream of the disconnect. One ring terminal on each battery stud; everything else lands on the busbars.

flowchart LR
  BATTP["Battery (+)
stud"]
  BATTN["Battery (−)
stud"]
  DISC["Blue Sea 6005
Disconnect"]
  PBUS["+ Busbar
Blue Sea 2300"]
  NBUS["− Busbar
Blue Sea 2300"]
  FRAME[/"Frame-Ground
Stud"/]
  CONV["PD9140A
Converter"]
  JACK["Jack
(30A fuse, Phase 07)"]
  BR1["Fused branches
blue / purple
yellow+brown"]
  BRK["Breakaway
(Session 02)"]
  BATTP -- "6 AWG" --> DISC
  DISC -- "6 AWG" --> PBUS
  PBUS -- "6 GA main" --> CONV
  PBUS -- "10 AWG" --> JACK
  PBUS -- "12-14 AWG" --> BR1
  PBUS -- "12 AWG" --> BRK
  BATTN -- "6 AWG" --> NBUS
  NBUS -- "6 AWG" --> FRAME
  CONV -. "ground return" .-> NBUS
  JACK -. "ground return" .-> NBUS
  BR1 -. "ground returns" .-> NBUS
  BRK -. "ground return" .-> NBUS
  classDef existing stroke:#a8a29e,stroke-width:1.5px,color:#a8a29e
  classDef new stroke:#ff8c42,stroke-width:3px
  classDef future stroke:#a8a29e,stroke-width:1.5px,color:#a8a29e,stroke-dasharray:5 3
  class BATTP,BATTN,DISC,CONV,BR1 existing
  class PBUS,NBUS,FRAME new
  class JACK,BRK future
  linkStyle 1,6,7 stroke:#ff8c42,stroke-width:3px
  linkStyle 0,2,4 stroke:#a8a29e,stroke-width:1.5px
  linkStyle 3,5,8,9,10,11 stroke:#a8a29e,stroke-width:1.5px,stroke-dasharray:5 3
      

30. Mount both busbars (Blue Sea 2300 × 2) on the V-nose wall or a backing board near the battery and disconnect. Use #10 (M5) screws into wood. Mount up off the floor where a dropped tool can't bridge to the frame. Positive and negative side by side.
31. Make the frame-ground stud. Pick a spot on the frame near the battery. Grind/sand the paint and rust down to bare shiny metal (about a 1" square). Bolt a stainless 1/4" or 5/16" bolt through with serrated/star washers biting into bare metal on both sides, or use an existing clean frame bolt. This is the ONLY bond between battery negative and the frame.
32. Wire the negative side. Battery (−) stud → 6 AWG cable → negative busbar stud 1 (1/4" ring terminal). Then negative busbar stud 2 → 6 AWG cable → frame-ground stud (1/4" ring terminal, dielectric grease the joint to seal it).
33. Wire the positive side. Battery (+) stud → existing 6 AWG cable → disconnect switch INPUT stud. Disconnect switch OUTPUT stud → 6 AWG cable → positive busbar stud 1. Then the heavy 6 GA SAE J1127 main feed (the one that goes to the PD9140A converter and main DC distribution) → positive busbar stud 2.
34. Re-land the 3 fused branches on positive busbar screws (#8 ring terminals, one per screw). Each branch keeps its existing 15A ATC fuse holder; only the fuse-feed end (the side that used to land on the battery positive) moves to the busbar.
    • Screw 1: blue wire branch
    • Screw 2: purple wire branch
    • Screw 3: yellow + brown wires branch
35. Route each branch's ground return to the negative busbar. If a branch previously grounded through the frame (chassis ground), run a dedicated return wire to a negative busbar screw instead. Single-point ground rule: nothing else bonds to the frame; everything returns through the negative busbar.
36. ABYC stacking rule: no more than 4 ring terminals stacked on any one stud or screw. You have 10 screw gangs on each busbar, plus 2 studs; spread the load out.
37. Torque, and read this carefully. Busbar fastener specs are in INCH-pounds, not foot-pounds, and they're far below the Lexivon's 25 ft-lb floor: 1/4"-20 studs ~60 in-lb (~5 ft-lb), #8-32 screws ~15 in-lb (~1.25 ft-lb). Your torque wrench cannot be used here. Either use an inch-pound driver, or hand-tighten snug with a nut driver. Brass strips easily; do NOT crank.
38. Snap both busbar covers on. Never run a busbar uncovered. The covers are your short-circuit protection from dropped tools and stray strands. Final check: every load grounds to the negative busbar (not the frame directly), each battery stud has exactly one ring terminal on it.

This is the longest phase. Take your time. Dedicated 30A circuit, not a tie-in to any existing branch.

flowchart LR
  PBUS["+ Busbar
screw 4"]
  FUSE["30A inline fuse
(within 18″ of busbar)"]
  GROMMET["V-nose floor pass-through
(1/2″ hole, grommet, silicone seal)"]
  TONGUE["Along tongue
(loomed at sharp edges)"]
  JACKP["Polestar jack
(+) input lug"]
  NBUS["− Busbar
screw"]
  JACKN["Polestar jack
(−) input lug"]
  PBUS -- "10 AWG red" --> FUSE
  FUSE --> GROMMET
  GROMMET --> TONGUE
  TONGUE --> JACKP
  JACKN -. "10 AWG yellow/white
(same path back)" .-> NBUS
  classDef existing stroke:#a8a29e,stroke-width:1.5px,color:#a8a29e
  classDef new stroke:#ff8c42,stroke-width:3px
  class PBUS,NBUS existing
  class FUSE,GROMMET,TONGUE,JACKP,JACKN new
  linkStyle 0,1,2,3 stroke:#ff8c42,stroke-width:3px
  linkStyle 4 stroke:#ff8c42,stroke-width:2.5px,stroke-dasharray:5 3
      

39. Plan the wire route from the positive busbar (after a new 30A inline fuse near the busbar) → through the V-nose floor → along the tongue → to the jack. Drilling through the floor is cleaner than going through the front wall for this trailer. Pick a spot in the V-nose floor with a straight shot to the tongue and clear of frame cross-members.
40. Drill the floor pass-through. 1/2" bit, drill from inside to outside. Deburr the hole, install a Vrupin rubber grommet, then a dab of silicone around the grommet underneath since the underside is weather-exposed.
41. Run the Ancor 124102 10/2 duplex cable from inside (near the busbar) through the grommet, along the tongue, to the jack. Leave 6-8" extra on each end. Loom (Alex Tech split loom) any sections that touch sharp metal edges.
42. Secure the cable with zip ties every 12-18 inches along the tongue.
43. Install the FEBRYTOLD inline fuse holder on the positive (red) conductor, within 18 inches of the positive busbar. Cut the red conductor, strip both ends, crimp each into one side of the fuse holder with a heat shrink butt connector. Heat shrink.
44. At the busbar end: crimp a #8 heat-shrink ring terminal onto the red conductor's free end (the side coming back from the fuse) and land it on a positive busbar screw. Same for the yellow/white conductor (negative): #8 ring terminal landed on a negative busbar screw. Don't rely on frame grounding through the jack's mounting bolts — run the actual wire.
45. At the jack end: connect to the Polestar's input lugs per the manual. Black wire (positive) → red conductor with ring terminal, white wire (ground) → yellow/white conductor.

flowchart LR
  BATTP["Battery (+)
cables connected"]
  DISC["Disconnect
flipped ON"]
  PBUS["+ Busbar live
~12.6-12.8V"]
  ALL["All loads live:
converter, jack,
fused branches, breakaway"]
  NBUS["− Busbar"]
  BATTN["Battery (−)"]
  AC["Generator + AC test
(breakers 6, 2)"]
  BATTP --> DISC
  DISC --> PBUS
  PBUS --> ALL
  ALL -. ground returns .-> NBUS
  NBUS --> BATTN
  AC -.-> ALL
  classDef pos stroke:#ff6b35,stroke-width:2px
  classDef neg stroke:#5b8aa0,stroke-width:2px
  classDef ac stroke:#fbbf24,stroke-width:2px
  class BATTP,DISC,PBUS,ALL pos
  class NBUS,BATTN neg
  class AC ac
      

46. Install the 30A fuse in the inline fuse holder. Snap the holder cover closed.
47. Reconnect the battery cables: positive first (which feeds the disconnect input via the new busbar), then negative.
48. Flip the disconnect switch to ON.
49. Test the jack: press UP. It should extend smoothly. Press DOWN. Steady motion, not slow or stuttering.
50. If the jack doesn't move: check the fuse, the switch (and the optional kill switch if installed), the connections, the battery voltage at the disconnect output stud (should be ~12.6V when ON).
51. Use the jack to lift the trailer off the F-250 ball and unhitch (or stay hitched and just verify extension/retraction range, whichever fits your next step better).
52. Cycle the jack up and down a few times to confirm smooth operation.
53. Test the AC unit (it stopped working before this session, see Common pitfalls / known issues). Plug in the Honda generator, confirm shore power is feeding the panel, flip breaker 6 (Recept / A.C.) ON if it isn't, try the AC. Diagnostic ladder if it still doesn't run:
    • Was breaker 6 tripped (middle position)? Reset it.
    • Was breaker 2 (Charger) tripped? Without 13.6V from the converter AND with the old dead battery, the AC's 12V control board would have starved. Now that the battery is fresh and the converter is fed again, the controls should wake up.
    • Still dead with both breakers on? Common failure on rooftop RV ACs is the start/run capacitor (~$15 part). What's the AC unit's brand and model?

54. Apply dielectric grease to all exposed terminals: battery studs, busbar studs and screws, disconnect studs, jack lugs, fuse contacts. Small amount, coat the metal.
55. Take photos of the completed install. Battery, busbars, disconnect, fuse holder, wire run, jack connections, frame-ground stud.
56. Wrap loose wire ends with electrical tape if any are exposed. Nothing dangling, nothing rubbing.

1. Unplug shore power first if connected to the Honda generator. Then flip the Blue Sea disconnect to OFF and verify 0V at the disconnect output.
2. Disconnect the trailer from the truck if hitched.
3. Open the existing Cesco junction box. Wide photo of the inside before touching anything.
4. Label every wire entering and exiting the box. Masking tape and Sharpie. Note color, function (verified by tester or multimeter, not assumed from color — see the wire color caveat in the system map at the top of this doc), and direction. If two wires are connected together, label both with the same function name.
5. Photograph each labeled wire for reference if a label falls off.

6. Cut the wires between the box and the trailer-side wiring. Cut on the box side, leaving 6-8" of fresh wire on the trailer side.
7. Cut the wires between the box and the 7-pin cable. Same approach: 6-8" of cable side, cut close to the box.
8. Remove the breakaway switch from its mount.
9. Remove the old breakaway battery. Don't throw it out yet, may need terminal layout reference.
10. Unbolt the old Cesco box from the A-frame. Note the mounting hole pattern.
11. Clean the mounting area on the A-frame. Wire brush rust, wipe with rag.

12. Test fit the new box in the same location. Mark new mounting holes if they don't match.
13. Drill new holes if needed. Apply rust-inhibitor primer to bare metal around the holes.
14. Bolt the new box to the A-frame with stainless or galvanized hardware. Serrated or lock washer to prevent vibration loosening.
15. Mount the new breakaway switch in the box per BUNKER INDUST instructions. Verify the pin pulls cleanly.
16. Install the new breakaway battery. Don't connect it yet.

17. Strip the trailer-side wires. About 3/8" of insulation off each end.
18. Match wire functions using your labels from Phase 01. Standard RV convention (verify before trusting): white = ground, brown = running, yellow = left turn/brake, green = right turn/brake, blue = electric brakes, red or black = aux 12V. Pair each trailer-side wire to its 7-pin-side counterpart by verified function.
19. For each verified match, use a heat shrink butt connector sized for the wire gauge: TICONN smaller (blue or red) for signal wires, Ancor 309225 yellow for the aux 12V wire.
20. Crimp each side with a firm squeeze using the ratcheting tool. Pull-test to verify.
21. Heat shrink each connector until adhesive flows out the ends.
22. Route the spliced wires neatly with small zip ties.

23. Route a new wire from the junction box to the battery area. 10 AWG or 12 AWG depending on run length.
24. Install a 20A inline fuse on this aux 12V wire within 18 inches of the battery positive terminal.
25. Terminate on the disconnect switch INPUT stud (the battery side), stacked alongside the existing battery (+) cable. Use a 3/8" heat-shrink ring terminal. The Blue Sea 6005 input stud is designed for multiple ring terminals; you may stack up to 4 per ABYC. Do NOT land this on the positive busbar (that's the load side of the disconnect).

26. Connect the breakaway battery in the box per the BUNKER INDUST diagram. The breakaway directly feeds the blue (electric brake) wire when activated.
27. Test the breakaway: pull the breakaway pin (with trailer disconnected from truck). Brakes should lock up. Try to push the trailer with an assistant - it shouldn't move. Reset by re-inserting the pin.
28. Charge the breakaway battery via the existing charge circuit (which now ties to the trailer battery via the new wiring).

29. Flip the disconnect switch ON.
30. Plug the trailer into the F-250.
31. Run the trailer light tester or have someone activate truck lights/brakes/turn signals. All circuits should work.
32. Test the jack still works (Session 1 wiring shouldn't have been touched).
33. Verify breakaway charge: ~12.6V across the breakaway battery terminals.

34. Apply dielectric grease to all terminals inside the new junction box.
35. Close the box lid. Make sure the gasket seals cleanly.
36. Photos. Inside before closing, outside after.

1. Flip the disconnect switch to OFF. Verify 0V.
2. Disconnect the trailer from the truck.
3. Open the BUNKER INDUST junction box.

4. Cut the old cable at the strain relief where it enters the junction box. Leave the trailer-side splices (done in Session 2) intact.
5. Pull the old cable out through the strain relief and away from the trailer.
6. Note the cable routing path: tongue route, clips, supports, strain relief location. New cable follows the same path.

7. Feed the new Hopkins 20246 through the strain relief on the junction box, plug end on the outside.
8. Route along the same path the old one took. 8 ft length should give plenty.
9. Don't tighten the strain relief yet. Adjust length once spliced.

10. Plug the new cable into the F-250.
11. Activate each circuit one at a time: running lights, left turn, right turn, brake, reverse. Use a helper or the 7-pin tester on the loose end.
12. Use the multimeter to identify which wire carries each signal. Label each: "GND", "TAIL", "LEFT", "RIGHT", "BRAKE", "AUX12V", "REVERSE".
13. Write down the color-to-function mapping for reference on future work.
14. Disconnect from the F-250 before splicing.

15. Cut the new cable's bare end to a length that lets splices sit neatly inside the box (typically 4-6" of stripped jacket exposed).
16. Strip 3/8" of insulation from each of the 7 conductors.
17. Splice each new-cable wire to the corresponding trailer-side wire with heat shrink butt connectors. Match by FUNCTION (per your labels), not color.
18. Heat shrink each splice. Adhesive flow visible at the ends.
19. Organize the splices with small zip ties.
20. Tighten the strain relief on the cable.

21. Reconnect the trailer to the F-250.
22. Walk through each circuit with the tester or a helper activating the truck:
    • Running lights → tail circuit lit
    • Left turn → left circuit flashing
    • Right turn → right circuit flashing
    • Brake pedal → brake circuit lit
    • Reverse → reverse circuit (if used)
    • Aux 12V → aux circuit lit (truck running)
23. Test electric brakes: with trailer plugged in, activate the truck's brake controller manually (most have a manual lever). You should hear brake magnets click.
24. Test breakaway one more time. Should still work.

25. Apply dielectric grease to the new cable's 7-pin plug pins. Prevents corrosion at the truck-trailer interface.
26. Apply dielectric grease to splices inside the junction box.
27. Close the junction box.
28. Photos. Inside and outside.

1. Inspect every wire run end to end. Look for chafing, sharp edges, exposed sections.
2. Install wire loom on any unprotected runs along the tongue or wheel wells. Slide split loom over the wire, zip tie every 12-18 inches.
3. Inspect every connection point: battery, disconnect, fuse holder, jack lugs, junction box splices, 7-pin plug. Apply dielectric grease where missing.

4. Label key components with permanent marker on masking tape:
   • "Trailer Battery: Renogy 100Ah AGM, installed [date]"
   • "Disconnect: Flip OFF for storage, ON for use"
   • "Aux 12V Fuse: 20A"
   • "Jack Fuse: 30A"
   • "Breakaway Battery: replace every 3-5 years"
5. Apply NOCO NCP2 to battery terminals if you haven't already.

6. Full photo set of completed system. Reference for future maintenance.
7. Update this document with completion date and notes from each session.

8. Short loop to a parking lot. Practice using the jack solo, then back. Verify:
   • All trailer lights work during the drive
   • No warning messages on the F-250 dashboard
   • Brakes work correctly when you brake the truck
   • Jack works smoothly to unhitch and re-hitch at home