TrCM+ Safe Parking

TrCM+ Safe Parking

'Safe Parking' is an additional function which ensures that upon disconnection of the air supply line (red coupling) the trailer parking brake is engaged.

TrCM+ General

Park and shunt valve with integrated emergency braking valve for the service brake system, as well as a pressure protection valve for auxiliary devices (e.g. air suspension) for twin-line air brake equipment in trailer vehicles.

'Safe Parking' is an additional function which ensures that upon disconnection of the air supply line (red  coupling) the trailer parking brake is engaged.


Valve Shunt  Valve
(black knob)
(red knob)
Trailer coupled Operation Conditions Service Brake System Park brake /
Spring brake System
pulled pushed (must be manually pushed) yes drive released released
pulled automatic pulled out no Trailer
Emergency function
Safety function:
Released via overload protection valve
pushed pushed no shunting released released
pushed pulled no Parking (uncoupled) released engaged
pulled pulled yes Parking (coupled) released engaged


Warning - Danger!
Before starting the journey, the spring brake cylinder must be released manually by pushing the park valve.


  • The TrCM+ is fixed to the vehicle chassis with two/three M 8 bolts.
  • The control knobs must be easily accessible.
  • Not used ports must be plugged.
  • For painting/coating all open ports must be protected to avoid penetration of the paint/coat.
  • For fittings / push-in fittings refer to the instructions of the respective manufacturer.


  1. System without pressure
    Shunt valve (black button) must be pushed in (securing the trailer vehicle previous to this test), park valve (red button) automatically pushed out.
  2. Initial charging
    Apply pressure to port 1; the shunt valve (black button) must go into the operating position (jump out). The park valve (red button) remains pushed out.
  3. Automatic emergency braking
    Lower the pressure at Port 1 to 0 bar; the port 21 emergency braking must activate automatically.
  4. Pressure protection valve
    Instructions for adjustment may be found in the fitting instructions, order no.: 000 314 012.
  5. park brake valve (red button)
    Apply pressure to port 1. park valve (red button) automatically pushed out, push the park valve (red button) in, at least 5.0 bar in the supply reservoir, pull the park valve (red button), port 2 (spring brake system) must vent down to 0 bar, vehicle braked.


According to legal registrating country requirements or the statutory regulations of § 29 StVZO. If defects are discovered, either during examination of the vehicle or when travelling, the valve must be replaced.
The cage filter 029 000 409 in Port 1 is to be exchanged when soiled or damaged.

Technical Data

Operating pressure: pe = 10 bar
Operating temperature: - 40°C - + 70°C
Medium: Air
Weight: ca. 1.8 kg
Pneumatic Port: 6 x M 16 x 1.5
2 x M 22 x 1.5
1 x M 12 x 1.5
Pressure protection valve DIN 74279 - C 6-22
Opening pressure: pe =  ca. 6.2 bar
Closing pressure: pe =  min 5.2 bar

Section Drawing

Please find a collection of coloured functional section drawings here.

Air flow Graph


Function symbol DIN ISO 1219


Port Description
1 inlet port (coupling head RED, supply line)
1-2 inlet/delivery port (reservoir)
2 delivery port (spring brake actuator)
3 exhaust (spring brake actuator)
4 control port (coupling head YELLOW, control line)
12 must be connected to port 21
21 delivery port (EBS/ABS)
22 plugged
23, 24, 25 delivery port (PPV = pressure protection valve, suspension)

For more technical information see: TÜV report No.: KO250.4E

Symbol used in drawings