KSB-221025 V3

Keystone RV
KSB-221025 A
Revision A-6/5/2023
End of Line (EOL) Resistor and Gateway Diagnostics
The information and instructions in a Keystone Service Bulletin (KSB) are intended to inform RV
dealership Service Managers/Technicians of situations that may occur with some Recreational
vehicles so dealership personnel can perform proper and efficient service. KSB’s are intended to
be used by trained RV technicians with the knowledge, tools and equipment to do the job properly
and safely, not “do-it-yourselfers”.
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Information is not presented as a repair guaranteed to be covered by warranty.
Keystone’s P & P (Policy & Procedures) must be followed for any requested warranty work.
Do not assume this repair is covered by warranty.
Not every unit listed requires a repair.
Symptom-There is no temperature reading on the iN∙Command® LCD Display Commander (DC)
or it displays a “-F” zone temperature. All other functions of iN∙Command® work as designed.
NOTE: If any or all other features of iN∙Command® display properly on the
DC, the issue is not iN∙Command® related. It can only be related to
the components of the A/C system or the parts, installation and/or
wiring by Keystone.
Model and Serial Numbers Included:
2021 - 2023
Alpine,
All Models
2021 - 2023
Cougar,
All Models
2020 - 2023
Raptor,
All Models
2020 - 2023
Montana,
Legacy Models with iN∙Command®
When performing this KSB, please make certain that appropriate Personal Protective Equipment
(PPE) is used.
The Gateway is a part of the A/C system that allows its components to communicate with the
iN∙Command® system. The End of Line (EOL) resistor is installed in the Gateway to provide signal
back to iN∙Command®, that there are no other A/C’s in the chain. If the EOL is missing or in the
wrong location, the symptoms described above can occur.
The RVC-Network Cables connects all A/C’s together in order to properly communicate with
iN∙Command®. They should be wired in this sequence:
1. DC to Main A/C (typically Center of unit) or Zone 1
2. Main A/C to 2nd A/C (if equipped) or Zone 2
3. 2nd A/C to 3rd A/C (if equipped) or Zone 3
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Components involved are located in Roof A/C cavity. See Figure 1.
Fig. 1
Note: Do not begin this diagnostic process unless there is no temperature reading or a “-F”
zone temperature reading on the DC right now.
1. Power reset. The Gateway can “go to sleep”. To wake it up, remove all power (12V & 120V)
from the unit for 60 seconds by unplugging the shoreline cord and turning off the Battery
Disconnect (if equipped) or removing he positive cable from the battery. After power is
restored, turn on the DC, if the symptom readings remain, proceed to step 2.
2. Verify the EOL Resistor is installed in the last A/C in the chain of A/C’s on this unit. (1. Roof
A/C-EOL in Gateway of the only A/C; 2. Roof A/C’s-EOL in Gateway of 2nd A/C; 3. Roof A/C’sEOL in Gateway of 3rd A/C) See Figure 2.
RVC-Network
Cable
EOL ResistorKRV #599204
Fig. 2
3. If the EOL is properly located and the conditions still exists, remove the iN∙Command® DC
from the wall, unplug the RV-C network cable coming from the Zone 1 A/C Gateway to the DC.
Check the resistance at the 2-pin connection with a multi-meter for a reading between
117Ω~123Ω (Ohms). This tests the entire chain of RV-C cables and connections for all Zones.
a. If not in this range, 1 or more of the RV-C cables is bad and/or 1 or more of the
connections is compromised somewhere in the chain. It will be necessary to isolate
each RV-C cable/connection, repeat the resistance test to find and correct the defect.
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4. If all RVC-Network cables have proper resistance, go to the A/C Controller for the Zone
showing ‘ - F°’. Remove the cover of the A/C Controller and verify the black “Zone Jumper” is
installed on the pins for the correct Zone (1, 2 or 3). See Figure 3.
Zones
Zone Jumper
Fig. 3
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5. If Zone Jumper is in correct Zone, then verify the wiring connecting the A/C Gateway to the
A/C Controller are attached to the correct terminals, spades are connected nice and tight,
wires are crimped tight to spades. See Figure 4.
Fig. 4
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6. If the problem remains, replace the A/C Gateway for the Zone showing the symptom readings on
the DC.
7. Last, a “Reset” is needed to clear all systems and components. Remove all power from unit by
unplugging shore cord, turning off battery disconnects for a minimum of one minute before
restoring all power, turning on battery disconnects. Test to verify symptom(s) no longer exists.
Over the next 24 hours, periodically validate correct readings on DC to confirm resolution.
WARRANTY REIMBURSEMENT
This KSB is for repair purposes only. If this is a warranty repair, the flat rate code is 7301642K
Submit a Pre-Authorization Key Express, Flat Rate Code # 7301642K with KSB # 221025 noted in the
customer complaint section and a detailed description of which steps were completed to resolve the
complaint. The time authorized is dependent on what diagnostics were required.
If you have questions, please contact your product team with questions:
Luxury
866-273-1450
Toy Haulers
866-273-1452
Cougar
866-273-1454