PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-46
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-46V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
5. TYRE FUNCTION
SYSTEM COMPOSITION
The tyre pressure monitor system consists of the following components:
–four sensors (one on each wheel but not on the spare wheel),
–a computer (UCH),
–an instrument panel display for the driver.
WARNING:
It is forbidden to install PAX System tyres on a vehicle without PAX System tyres as standard.
In the MEGANE II family, PAX System tyres can only be installed on the 5-seat SCENIC II.
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-47
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-47V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
SYSTEM OPERATION
–The valves are activated approximately 1 minute after the vehicle has been running at a speed above 12 mph
(20 km/h).
–During driving, the valves emit signals every minute.
–The valves remain active for 15 minutes after the vehicle stops, then switch to standby mode.
–In standby mode, the valves emit signals only if they detect a pressure difference between two successive
measurements exceeding 68 mbar or if the pressure difference since last emitting exceeds 68 mbar (due to tyre
cooling).
–The tyres are considered to be cold when the vehicle speed has been zero for 1h 45 min.
–The minimum time for detection of a leak is approximately 15 minutes.
–The message Inflate tyres for motorway is displayed only if the vehicle travels at more than 102 mph (170 km/
h) (as an indication) for 3 minutes and the pressure on at least one of the tyres is 400 mbar less than the
recommended pressure at low speed. This message is inactive if the tyres are inflated to motorway pressure,
irrespective of the vehicle speed.
–Alert thresholds:
–over-inflation when cold = recommended pressure + 700 mbar,
–over-inflation when hot = recommended pressure + 850 mbar,
–under-inflation = recommended pressure - 400 mbar,
–serious under-inflation = recommended pressure - 600 mbar,
–imbalance = difference in pressure between the left-hand and right-hand wheels on the same axle greater
than 500 mbar.
–Information messages for the driver:
–Stop! Tyre puncture + STOP warning light + wheel concerned is highlighted on instrument panel display +
buzzer.
–Adjust tyre pressure + the wheel concerned is highlighted on instrument panel display.
–Inflate tyres for motorway + four wheels highlighted on instrument panel display.
–Tyre sensor fault + the wheel concerned is erased.
–Electronic fault + "Service" warning light + the four wheels concerned disappear from the instrument panel
display.
–No display of the tyre inflation pressure on the instrument panel on MEGANE II.
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-48
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - System operation
87B
87B-48V9 MR-372-J84-87B000$129.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
MATCHING THE VALVE TO THE TYRE
Whenever wheels are swapped over, reprogram the new valve positions in the UCH using the diagnostic tool.
The coloured rings will then have to be placed back in the location marked on the label on the driver's door.
Ring colours:
–Front left-hand: green.
–Front right-hand: yellow.
–Rear left-hand: red.
–Rear right-hand: black.
WINTER AND SUMMER TYRES
On leaving the factory, it is the summer wheel set that is configured in the UCH, but customers can fit their vehicle
with a winter set (winter wheels = wheel rims + sensors + special tyres).
The first time a set of winter wheels is fitted, program the codes of the four valves. Thereafter, whenever the set of
tyres is changed, recognition is automatic without having to touch the UCH.
Establishing communication between the UCH and the CLIP diagnostic tool:
–Connect the wire to the diagnostic socket and switch on the ignition.
–Switch on the diagnostic tool.
–Select the vehicle type and carry out the multiplex network test.
–Select the Tyre function.
–Follow the fault finding procedure described previously.
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Configurations and programming
87B
87B-57
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Configurations and programming
87B
87B-57V9 MR-372-J84-87B000$215.mif
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
5/ TYRE PRESSURE MONITORING SYSTEM FUNCTION
5.1 PROGRAMMING PROCEDURE FOR THE 4 VALVE CODES (SC002)
SC002:
Programming the four valve codes
IMPORTANT:
Any operation involving the replacement of a wheel sensor, requires perfect knowledge of the
recommendations defined in Repair Manual 364 (for Mégane II) or 370 (for Scénic II), section 35.
●Inflate the four tyres to 3.8 bar.
●Establish communication with the UCH using the diagnostic tool.
●Select the Repair mode menu.
●Select the Programming menu.
●Select line SC002 in the Tyre function.
●The stored codes and valve sets detected are displayed.
●Select the Valve set selection menu, then Summer or Winter.
●Confirm to display the Valve programming conditions table.
●Confirm by selecting next to obtain the Find valve codes menu.
●Excite each valve by holding the valve exciter against the tyre just below the valve in question.
●Start with the front left-hand wheel.
●Wait for the new code to appear on the screen before moving on to the next valve.
●The order for programming the codes is as follows:
Front left-hand Front right-hand Rear right-hand Rear left-hand
●Click on the "Confirm" button to transmit the codes to the UCH.
●Inflate the tyres to the recommended pressures.
●Carry out a road test: speed > 12 mph (20 km/h) for 10 minutes.
●Check that no message appears on the instrument panel.
IMPORTANT:
When swapping wheels over, reprogram the UCH with the new valve positions using the diagnostic tool and
program the valve codes.
The coloured rings will then have to be placed back in the location marked on the label on the driver's door.
87B-385
AFTER REPAIRCarry out a complete check with the diagnostic tool.
V9 MR-372-J84-87B000$990.mif
87B
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
Note: In Vdiag 44 vehicles, the Service warning light comes on with the instrument panel message.
ALP 52"Adjust tyre pressure" message appears
(the wheel concerned is highlighted on the display)
NOTESCheck that all the faulty tyres are fitted with tyre pressure monitor valves.
Make sure the tyre has the recommended
pressure specified on the label or in the
driver's handbook (not under- or over-
inflated).
Are the tyres at the recommended
pressures?Readjust the tyre inflation pressure.
Read the pressures in PR003
to PR006.
Do PR003 to PR006 match
the readings taken with the
pressure gauge (to within
0.2 bar)?Read the recommended
pressures in the UCH
(PR009 to PR012)
Do the values of these
parameters match the
manufacturer's
recommended
pressures?Write the recommended
pressures with command
VP005 Enter
recommended
pressures.
Program the four valve codes and reinstall the coloured rings in the
position indicated on the label on the driver's side.
NO
YES
YES
NO
ANO
YES
UCH_V44_ALP52 / UCH_V48_ALP52 / UCH_V4C_ALP52 / UCH_V4D_ALP52 / UCH_V4F_ALP52 / UCH_V50_ALP52
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
87B-387
AFTER REPAIRCarry out a complete check with the diagnostic tool.
V9 MR-372-J84-87B000$990.mif
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
87B
UCH
Vdiag No.: 44, 48,
4C, 4D, 4F, 50
ALP 53"Adjust tyre pressure" message appears
(2 wheels are highlighted on the display)
Note:
In Vdiag 44 vehicles, the Service warning light comes on with the instrument panel message.
NOTESCheck that all the faulty tyres are fitted with tyre pressure monitor valves.
Is there a pressure
imbalance between the left-
hand and right-hand tyre on
the same axle?Check the positions of
the coloured rings
against the label on the
driver's side.
Program the four valve
codes and reinstall the
coloured rings in the
position indicated on
the label on the driver's
side. Have the front and rear
tyres been swapped?
Adjust the tyre pressure to the
manufacturer's recommended
levels.
Is the fault still present?End of fault finding.
NO
YESYES
NO
B
NO
YES
A
UCH_V44_ALP53 / UCH_V48_ALP53 / UCH_V4C_ALP53 / UCH_V4D_ALP53 / UCH_V4F_ALP53 / UCH_V50_ALP53