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V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of parameters
UCH
Vdiag No.: 44
87B
PR074
BATTERY SETPOINT VOLTAGE
NOTESNo faults should be present or stored.
Depending on the battery charge status, the operating phase and the battery temperature, the UCH determines
what the voltage across the battery terminals should be.
When the battery charge drops, and PR076 Battery voltage after rest decreases, the UCH can temporarily
increase the PR075 Alternator setpoint voltage by 1 V and for a period of 15 minutes after switching on + after
ignition feed.
Before and during starting, PR075 Alternator setpoint voltage is fixed at 10.7 V.
A maximum of 30 seconds after the engine has started, the UCH sets PR075 Alternator setpoint voltage to the
optimum value calculated.
The injection computer can also control the alternator (component code 103) regulation voltage.
The injection computer sends the maximum authorised power delivered by the engine, to the UCH via the
multiplex network.
If the power available by the engine is less than the power consumed by the alternator (component code 103),
the UCH reduces PR075 Alternator setpoint voltage.
In the event of a fault, perform a complete check on the battery and charging circuit (see 80A, Battery).
If the fault is still present, contact Techline.
AFTER REPAIRRepeat the conformity check from the start.
UCH_V44_PR074
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87B -149
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V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of parameters
UCH
Vdiag No.: 44
87B
PR075
ALTERNATOR SETPOINT VOLTAGE
NOTESNo faults should be present or stored.
Depending on the battery charge status, the operating phase and the battery temperature, the UCH determines
what the voltage across the battery terminals should be.
When the battery charge drops, and PR076 Battery voltage after rest decreases, the UCH can temporarily
increase the PR075 Alternator setpoint voltage by 1 V and for a period of 15 minutes after switching on + after
ignition feed.
Before and during starting, PR075 Alternator setpoint voltage is fixed at 10.7 V.
A maximum of 30 seconds after the engine has started, the UCH sets PR075 Alternator setpoint voltage to the
optimum value calculated.
The injection computer can also control the alternator (component code 103) regulation voltage.
The injection computer sends the maximum authorised power delivered by the engine, to the UCH via the
multiplex network.
If the power available by the engine is less than the power consumed by the alternator, the UCH reduces PR075
Alternator setpoint voltage.
In the event of a fault, perform a complete check on the battery and charging circuit (see 80A, Battery).
If the fault is still present, contact Techline.
AFTER REPAIRRepeat the conformity check from the start.
UCH_V44_PR075
Page 150 of 179
87B -150
MR-413-X44-87B000$720.mif
V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Interpretation of parameters
UCH
Vdiag No.: 44
87B
PR076
BATTERY VOLTAGE AFTER REST
NOTESNo faults should be present or stored.
The battery voltage after rest represents the battery charge status.
9 V < PR076 < 14 V
In the event of a fault, perform a complete check on the battery and charging circuit (see 80A, Battery).
If the fault is still present, contact Techline.
AFTER REPAIRRepeat the conformity check from the start.
UCH_V44_PR076
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V5
UCH
Vdiag No.: 44PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Customer complaints87B
ENERGY MANAGEMENT87B
NO + ACCESSORIES FEED ALP 26
NO + AFTER IGNITION FEED ACTIVATION OR
+ AFTER IGNITION FEED REMAINS JAMMEDALP 27
BATTERY WARNING LIGHT COMES ON ALP 28
STARTER NOISY ALP 29
LOW LIGHT INTENSITY ALP 30
SUNROOF87B
THE SUNROOF DOES NOT WORK ALP 31
MEMORY KEY87B
NO INFORMATION IN THE KEYFAULT
FINDING
CHART
32
EXTERNAL TEMPERATURE DISPLAY 87B
NO EXTERNAL TEMPERATURE DISPLAYALP 33
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V5
87B
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
ALP 1 No dialogue with the computer
NOTESCheck the condition and connection of the battery connections (see 80A Battery).
Check the condition of the fuses.
Check the battery voltage (see 80A Battery).
Repair if necessary (see MR 411 Mechanical 80A Battery).
Switch on the + after ignition feed.
Connect the diagnostic tool and perform the required operations.
Connect the diagnostic tool to another vehicle to check that it establishes dialogue correctly with the
vehicle. If dialogue is established correctly.
Check the multiplex network of the faulty vehicle (see 88B Multiplexing).
Check the connection between the diagnostic tool and the diagnostic socket (connection and cable in good
condition),
the computer supplies and the engine and passenger compartment fuses.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check the presence and condition of fuse F11 (20 A) on the passenger compartment fuse and relay box
(component code 1016). Replace the fuse if necessary.
Check the condition and connection of the connector of component 225 (tabs bent, oxidised or broken).
Check for + 12 V battery feed on connection BP19 of component 225.
Check for earth on connection MAM (for right-hand drive vehicles) or MAN (for left-hand drive vehicles) of
component 225.
Check for + after ignition feed on connections AP43, BP15, BPT, BP6, BP13, BP19, SP2, SP15 of
component 645.
Check for + 12 V accessories feed on connections SP2 and SP15 of component 645.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
AFTER REPAIRCarry out a complete check using the diagnostic tool.
UCH_V44_ALP1
MR-413-X44-87B000$912.mif
UCH
Vdiag No.: 44
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V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
UCH
Vdiag No.: 44
87B
ALP 26 Accessories feed not activated
NOTESCheck the battery voltage (see 80A Battery).
Start the fault finding procedure with the ignition off and the vehicle locked.
When the vehicle is unlocked, the instrument panel should light up for a moment.
Otherwise, carry out fault finding on the multiplex network (see 88B, Multiplexing).
Check the operation of status ET239 "Ignition switch position".
Check the presence and condition of fuses F27 (5 A), depending on the equipment, and F29 (15 A) on the
passenger compartment fuse and relay box (component code 1016).
Replace the fuse if necessary.
Check the condition and connection of the connectors of components 645 and 1016 (tabs bent, oxidised or
broken).
Check for + accessories feed on connection SP2 (for vehicles fitted with a manual gearbox) or SP15 (for
vehicles fitted with a sequential gearbox) of component 645.
Check for earth on connection NAM of component 645.
Check for earth on the connection MAM (for right-hand drive vehicles) or MAN (for left-hand drive vehicles) of
component 645.
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
Check the insulation, continuity and the absence of interference resistance of the following connections:
Connection code SP2 between components 645 and 1016.
Connection code SP15 between components 645 and 1016.
Connection code MAN or MAM between component 645 and earth MAN or MAM (depending on the driving
layout; right-hand or left-hand drive).
If the connection or connections are faulty and there is a repair procedure (see Technical Note 6015A, Electrical
wiring repair, Wiring: Precautions for repair), repair the wiring, otherwise replace it.
If the fault is still present, contact the Techline.
AFTER REPAIRCarry out a complete check using the diagnostic tool.
UCH_V44_ALP26
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V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
UCH
Vdiag No.: 44
87B
ALP 27No + after ignition feed activation or the + after ignition feed stays
jammed
NOTESCheck the battery voltage (see 80A Battery).
Check for faults using the diagnostic tool. Deal with the other faults first.
The + accessories feed activation function should be working; if not deal with ALP 26
Accessories feed not activated first.
Make sure that status ET239 Ignition switch position is working.
Make sure that status ET239 Ignition switch position
is workingApply the interpretation of the status if necessary.
Run a multiplex network test (see 88B, Multiplexing).
See 13B, Diesel injection or see 17B, Petrol injection.
AFTER REPAIRCarry out a complete check using the diagnostic tool.
UCH_V44_ALP27
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V5
PASSENGER COMPARTMENT CONNECTION UNIT
Fault finding - Fault Finding Chart
UCH
Vdiag No.: 44
87B
ALP 28 Illumination of the "battery charge" warning light
NOTESCheck the battery voltage (see 80A Battery).
Check for faults using the diagnostic tool.
Deal with the other faults first.
Check with LC023 Engine type that the engine type configured matches the vehicle. Otherwise perform CF028
Engine type to modify the configuration.
IMPORTANT
The battery warning light can flash if a low battery charge is detected (no-load voltage less than 12.2 V: voltage
measured during technical use) for the first 12 miles (20 km), then the warning light stops flashing. Also, the magic
eye of the battery (the hydrometer) is black.
If a vehicle has been driven less than 12 miles (20 km), the battery warning light is flashing and the battery magic
eye (the hydrometer) is black, apply the following procedure:
-Recharge the battery for at least 6 hours. The battery must be disconnected (reconnection must be done to torque).
Note:
The battery must be recharged using a specific charger, which is listed in the "Garage Equipment" catalogue.
-After 6 hours, if the magic eye has not turned green, the battery must be replaced.
If the configuration is correct (see 80A Battery).
If the fault is still present, contact the Techline.
AFTER REPAIRCarry out a complete check using the diagnostic tool.
UCH_V44_ALP28