Firefly G12 Communication to Water Heater
Bulletin Type:

TSB

Publication
Date:

May 2026

Bulletin #(s):

26-009

Make(s):

Jayco & Entegra Coach

Job Code(s):

9803650

Model(s):

Flat Rate(s):

9803650A - 0 .10 HR – G12
Harness Board Wiring
Inspection Only
9803650B - .50 HR – G12
Harness Board Wiring
Inspection and Repair

Accolade, Seneca
Accolade XT, Seneca XT
Vision XL, Precept

Incident:
Affected Units:
Parts Kit: N/A
Misc. Tools & Supplies:

Model Year(s):

2026

G12 is causing a fault in the system when the Suburban Water Heater
is operated from the Firefly screen.
2026 Jayco Seneca, Seneca XT, Precept & 2026 Entegra Coach
Accolade, Accolade XT, Vision XL
Parts Kit #: N/A
N/A
Screw Gun with Square Head Bit
Wire Strippers
De-pinning Tool
15A Blade Fuse

Parts Return Information: N/A

G12 COMMUNICATION INSPECTION
1. Proceed with the repair if a 15A
blade fuse is not installed in
position 8 in the front side of
the load center as shown in
Figure A.

26-009_TSB Firefly G12 Communication

Fig. A

May 2026

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G12 COMMUNICATION REPAIR INSTRUCTIONS
1.

2.

Locate the Firefly touch screen or control panel
in the coach, extend the bed slideout fully so the
bed base is fully accessible.
Using a screw gun and square head bit, remove
the fasteners securing the bed panel and
plywood to the front of the bed base over the
load center.

!

WARNING

!

Indicates a potentially hazardous situation that, if not
avoided, may result in death or serious injury.

!

WARNING

3.

Locate the plug for the G12 harness. (Figure 1)

4.

Using a de-pinning tool, remove the pin in Pin 9 (14 AWG orange), of the G12
Harness. NOTE: If you do not have a de-pining tool, you can use wire
strippers/cutters and cut the orange wire at the base of the plug. (Figure 2)

!

Ensure all power to the coach has been disconnected
and the coach is fully powered off, prior to starting
the repair.

Fig. 1

5.
6.

Use wire cutter/strippers, to remove the pin from the end of the 14 AWG
orange wire. (Figure 3)
Strip the end of the orange wire. (Figure 4)

Fig. 4

26-009_TSB Firefly G12 Communication

May 2026

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7.

Locate the 14 AWG Black wire, for fuse position 8, in the load center. (Figure 5)

Fig. 5

8.

Wago the 14 AWG orange wire in with the 14 AWG black wire. (Figure 5)

9.

Add a 15A blade fuse to position 8 in the front side of the load center and add a label on the inside of the door for
“Water Heater”. (Figure 6)

10. Re-secure the plywood and panel to the bed base with the same fasteners that were removed in step 2.

Jayco’s sole obligation under our limited warranty is to repair or replace defective materials and/or workmanship deemed our responsibility as determined
by Jayco in our sole discretion. Jayco reserves the right to use new and/or remanufactured parts or materials of similar quality to complete any work, and to
make parts and/or design changes as appropriate without notice to anyone. Jayco designs and/or materials changes are done without obligation to
incorporate such changes in previously manufactured product. Jayco makes every reasonable effort to ensure field remedies will not adversely affect
performance and/or safety of the unit. This field remedy is not intended to extend to future performance of this RV, or any of its materials, components or
parts beyond the standard warranty period. The RV owner’s obligation to notify Jayco, or one of its independent, authorized dealers, of a claimed defect
does not modify any obligation placed on the RV owner to contact Jayco directly when attempting to pursue remedies under state or federal law.

903 South Main Street • P.O. Box 460 • Middlebury, IN 46540

26-009_TSB Firefly G12 Communication

May 2026

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26-009_TSB Firefly G12 Communication

May 2026

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26-009_TSB Firefly G12 Communication

May 2026

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