FIELD SERVICE CAMPAIGN – 24111R1
09 December 2024
SUBJECT:
Coolant hose reroute for the cabin heater.
MODELS INVOLVED:
IC Bus® Electric CE Series buses.
REASON FOR REVISION:
Added section and parts for heat exchangers with shutoff valve (feature 48PPP). Added
image showing correct installation of parts for the overall cabin heater system. Revised
steps and images throughout the document for consistency and clarity.
DEFECT DESCRIPTION:
Certain IC Bus® Electric CE Series buses may have incorrect coolant hose routing for
the cabin heat which may cause coolant to leak from the cabin heat surge tank overflow
hose.
ELIGIBILITY:
This procedure applies ONLY to vehicles marked in the International® Service PortalSM
with FSC 24111. Also complete any other open campaigns listed on the Service Portal
at this time.
TOOLS REQUIRED:
Description
Coolant Management Tool
Cooling System Adapter
High-Voltage Personal Protective Equipment (PPE)
including Class 0 electrical insulating gloves (Red Label),
Electrical Hazard (EH) rated safety shoes / boots, flame
resistant clothing, and face shield

Tool Number
KL5007NAV
09-040-03
N/A

Table 1 Tools Information

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Page 1

PARTS REQUIRED:
Part Number

Part Description

8900381R91
N/A

Quantity

Kit, Cabin Heat Plumbing

1

1 x 5/8-in Adapter (source locally)

2

Table 2 Parts Information
8900381R91 contains the following parts:
Item

Part Number

Part Description

1

L2643485

2

3817028C1

3

L2643493

4

4310950C1

5

L2643493

6

L2643493

7

4421530C1

Hose, Heater, PSGR 90-degree 5/8 in

1

8

3878141C1

Adapter, Double 5/8-in Hose Barb

1

9

2643485R1

Hose, Heater, 5/8-in ID Premium

49.7-in (1263 mm)

10

1622034C1

Clamp, Air Duct Hose, 0.81–1.50-in

10

11

1514759C1

Clamp, Rad Inlet Hose,13/16–1-1/16-in

6

Hose, Heater, 5/8-in ID Premium
Hose, Heater, Bus Body
Hose, Heater, 1-in ID Premium
T-fitting, 1 x 1 x 5/8 in

Length / Quantity
18.3-in (465 mm)
1
2.95-in (75 mm)*
9.84-in (250 mm)**
2

Hose, Heater, 1-in ID Premium

2.4-in (61 mm)*
5.15-in (131 mm)**

Hose, Heater, 1-in ID Premium

49.2-in (1250 mm)*
65.0-in (1651 mm)**

* Hose length for vehicle with shutoff valve (feature 48PPP).
** Hose length for vehicle without shutoff valve.

NOTE: Hoses in the kit will need to be cut to size as required in each step.

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Page 2

Figure 1. Driver Heater Hose Parts (Configuration Without Shutoff Valve Shown)

WORK INSTRUCTIONS
GOVERNMENT REGULATION: Engine fluid (oil, fuel, and coolant) may be a
hazard to human health and the environment. Handle all fluid and other
contaminated materials (such as filters and rags) in accordance with applicable
regulations. Recycle or dispose of engine fluids, filters, and other contaminated
materials according to applicable regulations.
WARNING! To prevent personal injury and / or death, or damage to property, park
vehicle on hard flat surface, turn the engine off, set the parking brake, and install
wheel chocks to prevent the vehicle from moving in both directions.
WARNING! To prevent personal injury and / or death, always wear safe eye
protection when performing vehicle maintenance.
WARNING! To prevent personal injury and / or death, or damage to property, keep
flames or sparks away from vehicle and do not smoke while servicing the
vehicle’s batteries. Batteries expel explosive gases.

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Page 3

WARNING! To prevent personal injury and / or death, or damage to property,
remove the ground cable from the negative terminal of the battery before
disconnecting any electrical components. Always connect the ground cable last.
WARNING! To prevent personal injury and / or death, wear and use approved
high-voltage Personal Protective Equipment (PPE) when near a high-voltage
electric vehicle. Inspect PPE before use. Do not use gloves or other PPE with
expired dates, holes, cracks, or damage. NEVER touch energized ORANGE highvoltage cables or high-voltage components without wearing approved highvoltage PPE.
WARNING! To prevent personal injury and / or death, read all information in the
Safety Information and High-Voltage Safety sections of the service manual.
1. Park vehicle on a dry, level surface.
2. Put drive mode selector in Park or Neutral and set parking brake.
3. Turn ignition to Key OFF position.
4. Install wheel chocks.
5. Turn 12V disconnect switch OFF.
6. Perform High-Voltage Isolation Level 1. Refer to appropriate service manual for
detailed procedure.
7. Perform coolant drain procedure on the cabin heater coolant system. Refer to
appropriate service manual for detailed procedure.
8. Remove the driver heat exchanger trim and closeout panels to gain access to the
cabin heat supply and return hoses. Make note of which hose is supply and return
connecting to the underseat heater.
9. Check if the the hoses at the front of the heat exchanger have a shutoff valve
(feature 48PPP).
a. Yes: Continue to Step 10. See Replacing and Routing Supply Hoses at
Front of Heat Exchanger (WITH Shutoff Valve, Feature 48PPP).
b. No: Proceed to Step 21. See Replacing and Routing Supply Hoses at
Front of Heat Exchanger (WITHOUT Shutoff Valve).
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Page 4

Replacing and Routing Supply Hoses at Front of Heat Exchanger (WITH Shutoff
Valve, Feature 48PPP):
Perform the following steps for buses with a shutoff valve near the front of the heat
exchanger (feature 48PPP).

Figure 2. Hose Routing (Front of Heat Exchanger With Shutoff Valve)
1.
2.
3.
4.
5.
6.
7.
8.
9.

1-in clamp
2.95-in (75 mm) length of 1-in hose
1 x 1 x 5/8-in T-fitting
2.4-in (61 mm) length of 1-in hose
49.21-in (1250 mm) length of 1-in hose
5/8-in clamp
90-degree 5/8-in hose
5/8-in double barb adapter
49.72-in (1263 mm) length of 5/8-in hose

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Page 5

10. With cooling system completely drained, disconnect the return coolant hose at the
cowl.
11. Install 49.21-in (1250 mm) length of 1-in hose (Figure 2, Item 5) on the coolant
return port on the cowl.
12. Remove and discard the coolant supply hose between the shutoff valve and the
driver heat exchanger.
13. Install 2.4-in (61 mm) length of 1-in hose (Figure 2, Item 4) at the shutoff valve
outlet. Secure with 1-in clamp (Figure 2, Item 1).
14. Install 1 x 1 x 5/8-in T-fitting (Figure 2, Item 3) behind the 2.4-in (61 mm) length of
1-in heater hose. Position the T-fitting at the 6 o’clock position. Secure with 1-in
clamp (Figure 2, Item 1).
15. Install 2.95-in (75 mm) length of 1-in hose (Figure 2, Item 2) between the T-fitting
and driver heater inlet. Secure with 1-in clamp (Figure 2, Item 1).
16. Install 90-degree 5/8-in hose (Figure 2, Item 7) at the 5/8-in connection on the Tfitting. Secure with 5/8-in clamp (Figure 2, Item 6).
17. Install the 5/8-in double barb adapter (Figure 2, Item 8) to the 90-degree 5/8-in hose
(Figure 1, Item 7). Secure with a 5/8-in clamp (Figure 2, Item 6).
18. Install 65.0-in (1651 mm) of 5/8-in heater hose (Figure 2, Item 9) to the double barb
adapter (Figure 2, Item 8). Secure with a 5/8-in clamp (Figure 2, Item 6).
19. Route the heater hose toward the outlet at the rear of the driver heat exchanger.
20. Proceed to Step 30. See Replacing and Routing Supply and Return Hoses (Rear of
Heat Exchanger).

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Page 6

Replacing and Routing Supply Hoses at Front of Heat Exchanger (WITHOUT
Shutoff Valve):
Perform the following steps for buses without a shutoff valve near the front of the heat
exchanger.

Figure 3. Hose Routing (Front of Heat Exchanger Without Shutoff Valve)
1. 9.84-in (250 mm) length of 1-in hose
2. 1 x 1 x 5/8-in T-fitting
3. 5.15-in (131 mm) length of 1-in hose
4. 90-degree 5/8-in hose
5. 5/8-in double barb adapter
6. 65.0-in (1651 mm) length of 5/8-in hose

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Page 7

21. Disconnect existing coolant supply hose between the firewall and driver heat
exchanger.
22. Install 5.15-in (131 mm) length of 1-in hose (Figure 3, Item 3) at the firewall. Secure
hose with a 1-in clamp.
23. Install 1 x 1 x 5/8-in T-fitting (Figure 3, Item 2) to the 5.15-in (131 mm) length of
hose. Rotate T-fitting to 6 o’clock position (with 5/8-in port pointing downward).
Secure with 1-in clamp.
24. Install 9.84-in (250 mm) length of 1-in hose (Figure 3, Item 1) between the T-fitting
(Figure 3, Item 2) and the driver heater inlet. Secure hose with 1-in clamps.
25. Install the 90-degree 5/8-in hose (Figure 3, Item 4) to the 5/8-in port on the T-fitting
(Figure 3, Item 2). Secure with a 5/8-in clamp.
26. Install the 5/8-in double barb adapter (Figure 3, Item 5) to the 90-degree hose.
Secure with a 5/8-in clamp.
27. Install 65.0-in (1651 mm) of 5/8-in heater hose (Figure 3, Item 6) to the 5/8-in
double barb adapter (Figure 3, Item 5). Secure with a 5/8-in clamp.
28. Route the heater hose toward the outlet at the rear of the driver heat exchanger.
29. Proceed to Step 30. See Replacing and Routing Supply and Return Hoses (Rear of
Heat Exchanger).

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Page 8

Replacing and Routing Supply and Return Hoses (Rear of Heat Exchanger):
Perform the following steps for all hose configurations.

Figure 4. Hose Routing Behind Heat Exchanger
1. Bus body hose
2. Driver heat exchanger outlet
3. 1-in coolant return hose
4. 1 x 1 x 5/8-in T-fitting
5. 49.7-in (1263 mm) length of 5/8-in hose
6. 18.3-in (465 mm) length of 5/8-in hose
7. 1 x 5/8-in adapter

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Page 9

30. Disconnect the existing 1-in hose from the driver heat exchanger outlet (Figure 4,
Item 2).
31. Install bus body hose (Figure 4, Item 1) on the driver heat exchanger outlet (Figure
4, Item 2). Secure hose with 1-in clamp.
32. Install 1 x 1 x 5/8-in T-fitting (Figure 4, Item 4) between the bus body hose (Figure
3, Item 1) and the 1-in coolant return hose (Figure 4, Item 3). Secure with 1-in
clamps.
33. Install 18.3-in (465 mm) length of 5/8-in hose (Figure 4, Item 6) to the 5/8-in port on
the T-fitting (Figure 4, Item 4). Secure with 1-in clamp.
34. Install 1 x 5/8-in adapter (Figure 4, Item 7) to 5/8-in coolant return hose (Figure 4,
Item 6). Secure with 5/8-in clamp.
35. Cut the 1-in return hose connected to the underseat heat exchangers leaving
enough length to connect to the 1 x 5/8-in adapter installed in the previous step.
Secure with 1-in clamp. Discard length of 1-in hose that was cut off.
36. Install 1 x 5/8-in adapter (Figure 4, Item 7) to 5/8-in coolant supply hose (Figure 4,
Item 5). Secure with 5/8-in clamp.
37. Cut the 1-in supply hose connected to the underseat heat exchangers, leaving
enough length to connect to the 1 x 5/8-in adapter installed in previous step. Secure
with 1-in clamp. Discard length of 1-in hose that was cut off.
38. Proceed to Step 39 (see Completion).

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Page 10

Figure 5. Hose Routing Example (Front of Heat Exchanger)

Figure 6. Hose Routing Example (Rear of Heat Exchanger)

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Page 11

Completion:
39. Perform coolant system fill procedure. Refer to appropriate service manual for
detailed procedures.
40. Perform cooling system pressure test on cabin heater circuit and inspect for leaks.
Refer to appropriate service manual for detailed procedures.
41. Reinstall driver heat exchanger trim and closeout panels.
42. Reconnect High-Voltage Isolation Level 1. Refer to appropriate service manual for
detailed procedure.
43. Turn 12V disconnect switch ON.
44. Close and latch hood.
45. Remove wheel chocks.

LABOR INFORMATION
Operation number must appear on all claims.
Operation Number

Description

Time

A40-24111-1

Coolant valve reroute

3.0 hrs

Table 3 Labor Information

WARRANTY CLAIMS

Warranty claim expense is to be charged to Warranty. Claims are to be submitted in the
normal manner, making reference to Field Service Campaign 24111.
Section 7 of the Warranty Policy and Procedures Manual contains further information
related to the submission and processing of AFC / Recall claims.
As with all claim submissions, items acquired locally must be submitted in the “Other
Charges” tab. The cost of any bulk items (such as a bag of cable tie straps, roll of wire,
barrel of oil, or tube of silicone) should be prorated for the cost of the individual pieces /
amount used during each repair.
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Page 12

To make sure this important improvement is made in a timely manner, all claims for
24111 activity must be submitted by 30 September 2025 or within the normal warranty
period for the component repaired, if after 30 September 2025.

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Page 13