IMPACT 4.04.
11 06/03/2018
Chassis ID Path
87/Technical Service Bulletins//Parking heater, blocked
Model Identity
FH (4) 134292154
Publish date ID/Operation
17/11/2015 V-87-128
Parking heater, blocked
Technical Service Bulletin V-87-128
Valid for
Volvo FH(4), FM(4)
Case description
Parking heater does not start; green light in switch goes out after ~5 seconds. Information valid for both PH-CAB2 and
PH-ENGCA.
Reason
This phenomenon indicates that the parking heater has gone into blocked mode. This is a legal requirement and
occurs after too many unsuccessful start attempts (different number of attempts depending of reason). The most
common reason is lack of fuel, too much air in the fuel lines or similar. For this reason the parking heater goes into
blocked mode after 10 attempts.
Note: DTC B150C97 indicates that the parking heater is blocked but it seems like a blocked parking heater not always
has to have an active DTC.
Copyright to this documentation belongs to the Volvo Group. No reproduction, copying, change, amendment or other similar disposal is entitled without prior written consent by
the Volvo Group
The information contained herein is current at the time of its original distribution, but is subject to change. The reader is advised that printed copies are uncontrolled.
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IMPACT 4.04.11 06/03/2018
Action
Possible ways to reset the parking heater.
By removing a fuse:
1. Fit the plastic grip tool on Fuse number 69.
2. Activate the parking heater start switch and count 1, 2, 3, 4. At 4 remove the fuse. (The fuse must be
disconnected at least 10 seconds).
(the only time limit for unblocking the parking heater is between 4.2 seconds to 4.9 seconds after the start switch
is activated)
Re fit the fuse and try to start the parking heater. If it shuts down (the green diode in the switch) goes out after 5
seconds the parking heater is still in the blocked mode.
Then you have to try again until you succeed.
By using Webastos diagnostic tool. (can be ordered from a local Webasto agent)
By replacing the parking heater ECU. (the blocking is done in the parking heater ECU)
Warranty information
TSB actions Truck within warranty Truck outside warranty
In the event of failure Volvo Trucks pays warranty costs Volvo Trucks does not pay
As a preventive measure Volvo Trucks does not pay Volvo Trucks does not pay
Issued by
Truck Technical Service
Copyright to this documentation belongs to the Volvo Group. No reproduction, copying, change, amendment or other similar disposal is entitled without prior written consent by
the Volvo Group
The information contained herein is current at the time of its original distribution, but is subject to change. The reader is advised that printed copies are uncontrolled.
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