Skip to content

Sunny Shanghai Volkswagen car body control unit circuit analysis and troubleshooting (3)

(Receive Last Issue)

Case 2

Failure phenomenon: a 2009 production of 1.6 L Sunny sedan with manual transmission mileage of 1 356 km, the user reflecting the central locking function fails.

Analysis examination: central locking function by maintenance personnel, can not be found using the remote control of the central locking opening and closing, can not open the luggage compartment, insert the key in the driver’s door the lock cylinder, the door can not lockout / unlock. Blocking the radio signal due to the driver’s door key cylinder switch / unlock signal of the remote controller while the probability of failure is extremely small in the supply of electricity failure should the BCM.
with a test lamp examination, and found to be central locking BCM power SC49 blown fuse, the fuse replaced with a new test for the door lock, door lock motor operation, but the motor is not unlocked response attempt, again fuse SC49 .
into the connector J519 VAS5052 failure diagnostic inquiry, there are a fault code: 00329mdash; mdash; tailgate unlock start shorted to ground, there currently exist. Now the measured value area 041 Group 4, central locking state of the terminal 30 is powered ldquo; abnormal rdquo ;. According to prompt fault code, remove the luggage compartment open motor single test, the motor is working properly, it seems the point of failure on the line. When the key to find the luggage compartment opening with an interference wire harness moving part, found on the left side of the wire harness fixing clip off the trunk lid, the wire harness from the trunk open spring contact, has been worn, the motor is turned on so that the luggage compartment and the power source line V53 ground line short circuit is caused.

Troubleshooting: line breakage of insulating treatment, re-wrap the wire harness is fixed, the replacement of the fuse, central locking function returned to normal.

Case 3

Failure phenomenon: a 2008 production of 2.0 L Sunny sedan with automatic transmission, mileage 43000 km, users reflect The engine can not be started. Maintenance inspection personnel to the scene, the starter can not be found in the starting rotation position of the ignition switch, the engine can not be started, then the car towed back to the pits.

Analysis examination: examination revealed basic maintenance personnel, in addition to the phenomenon described user, turn signal lamp, emergency flashing warning lights, brake lights, down lights, wipers, horn, power windows, interior lights and lock functions have been disabled. With the remote control or the ignition key can not door lock / unlock, press the button on the operating unit and the air conditioning blower speed adjustment knob is rotated, no response.

As a vehicle body plurality of electrical failure simultaneously, should be related to the BCM. VAS5052 connected fault diagnostic, self-diagnostic function click to open a list of gateways, the engine control unit and the display are faulty BCM control unit list. The engine control unit fault code is: 01320mdash; mdash; and HVAC (air-conditioning) control unit loses communication currently exist. BCM malfunction code nine, namely: 03435mdash; mdash; room lamp / disconnection parking lamp terminals 30 currently exist; 00329mdash; mdash; tailgate unlock start shorted to ground, there currently exist; 03396mdash; mdash; in the control breaking the lock power supply terminal 30, currently exists; 00920mdash; mdash; driver-side and passenger-side rear view mirror heating circuit, currently exists; 03580mdash; mdash; heated outside mirrors terminal disconnection currently exist; 03585mdash; mdash; stop windscreen wiper open circuit terminal 30, currently exists; 03444mdash; mdash; ignition starter switch signal is not reliable, occasional; 03591mdash; mdash; horn Tripping currently exist; 03592mdash; mdash; horn breaking terminal 30, currently exists. Click the button to view the environmental conditions the control unit, the mileage at the time of each identified fault memory, the fault code occur simultaneously.

The fault code to copy the disc stored U, delete the fault memory. Detector left of the screen text prompts appear as follows: Cancel function does not meet the requirements. Click output diagnostic test mode (DTM) options for turn signals, wiper, horn functional testing, the top left of the screen appears again to cancel the function does not meet the requirements of the text prompts. Click measurement function to measure Now group 001 is OFF (ignition switch D / 86s terminalSignal), Off (D / 50 terminal signal), the opening (D / 75 terminal signal), Off (D / 15 signal terminal). When the ignition switch is in the ON position normal value should be open, closed, open, open. Now group 040, group 041 of eight J519 supply line 30, the measured value of the terminal, the normal order (turn signal / brake lights), the abnormality (internal light), abnormal (windshield wiper), normal (after windshield heating), abnormal (outside mirrors), the abnormality (horn signal), normal (reversing lights) and abnormal (central-control). Check the fuse for abnormal BCM power supply S18, S19, S49 and S50,4 fuses were normal. BCM enters using function block guide options, such as clicking the list above (FIG. 16) the measured values, find the case 30 of the power supply terminal status BCM 8 were normal, but the line 86s and 15 still abnormal.

observed

16

003 set is a measure of the wiper switch E22 and E38 of the intermittent wipe regulator, and E22, respectively, E38 placed in different gear, the measured value is not in operation is switched on, the measured value of the intermittent wipe display controller 1-4 changes, but no response to the wiper motor (FIG. 17). 012 group zone 1 and 3 are signal measurements left front and right front power window switch E40 to E81 power window switch, pressing the switch, the input signal is displayed, but the power window does not move, although these indicate BCM receives a switching signal but no output command. 005 is a group of four measurements door switch, showed off sequentially open the doors, no change in the display. Display group 007 4 door lock / unlock the real-time status. See four doors are in the unlocked state, the measurement values ​​of the four display area: unlocking, locking, unlocking, locking. Sequentially pressing the door stripping, the measured value does not change, indicating that the switch does not recognize some BCM signal. 015 is a measure of group 1 and the output signal of the fob. When operating the remote control locking / unlocking button, a display area can receive a corresponding radio signal. Left and right turn signal was observed with the locking / unlocking of the flashing prompts, but the central locking but no response.

17

Measurement D / 15 to the harness-side connector J519 T73a / 44 terminals of the power supply line,Normal lighting test light can be described on the 15th line power is supplied.

The above inspection was confirmed BCM damaged, for three reasons: First, line 15 BCM peripheral supply line normal, but the detection value is abnormal, indicating that the internal BCM power system failure ; Second BCM are not recognized by the switching signal; Third BCM identified certain switching signal, but not a control command to the actuator output. And the use of diagnostic and delete fault diagnostic test mode (DTM) operations were rejected, indicate that there is a problem inside the BCM.

18

Troubleshooting: maintenance personnel with VAS5052 guiding function reads the original vehicle length codes in the fault the BCM (FIG. 18), the replacement the new BCM, the BCM read out the original car length coding copied to the new BCM. Start the engine, the car smoothly. BCM off mode for the next production operation and re-matching remote control of various functions managed eleven BCM check verification, validation troubleshooting. At the same time the air conditioning system also returned to normal.

Review and Reflection: Contact between BCM only for the air conditioning system electrical load management, replacement ago BCM enters J533 data bus control unit, reads out the relevant set of 132 measurements communication automotive air conditioning system, shown as air conditioning to sleep. But BCM cause any damage on the button operation unit are ineffective air conditioner, but it is recognized that the present embodiment exclude new fault obtained.

Case 4

Failure phenomenon: a 2009 annual Sunny 1.6 L manual transmission car, mileage of 10,000 km. Users reflect the car horn does not ring.

Analysis check: Check maintenance staff confirm the presence of the fault, fault diagnostic VAS5052 connected into self-diagnostic function option, the control unit queries BCM no fault memory. Using the diagnostic test mode (DTM) terminal detection function for the speaker, the speaker emits beep, indicating the line between the horn to the horn itself BCM were normal. Now measurement signal input 033 of the horn button group 4 H region, the measured value is not always displayed operation indicating signal is not input BCM. Horn button is connected to the line by the BCM AnnF138 airbag spiral cable realized. Left and right turn the steering wheel, while pressing the horn button and the horn chirping occasionally appear, indicating the presence of intermittent disconnection F138. Remove the turn signal switch T41 white compositions connector, harness side T41 / 10 terminal (19) connected to the lead wire, analog ground intermittent operation the horn button, a speaker beep normal, thus confirming F138 problem.

19

Solution: Replace the airbag spiral cable F138, troubleshooting.

Case 5

Failure phenomenon: a 2009 annual Sunny 1.6 L sedan with automatic transmission, with mileage of 12,000 km, the user reflect the wiper does not work, and determine fault in one Windscreen washer after the spray appears.

Check Analysis: Taking into account the respective wiper gear do not work, for the maintenance staff checks first wiper power fuse, a fuse found SC40 (10 A) is blown, which causes each wiper switch signal can not stop enter the BCM. The description of the user, after exchanging the fuse, respectively, intermittent, low speed and high speed test, the normal operation of the wiper, the windshield washer switch E44 disposed spray work gear, only to hear the “popping” sound again SC40 fuse, thereby determining windscreen washer pump motor V5 line where there is a fault.
Instead of a fuseholder SC40 inserted short-circuit detector, the E44 Windscreen washer disposed gear, the test lamp lighting circuit detector. V5 connector disengagement, test lamp remains lit, indicating that the short circuit or an internal circuit E44. Check the V5 connector near the line no problem, refitted V5. Remove the steering in combination with the wiper switch, found T41 / 20 T41 harness connector jack white side, directly after the 12 V power plus the same specification fuse protection assay (FIG. 20) in the receptacle, the spray pump motor work, there is no fuse blown, indicating the absence of short-circuit line, the short-circuit point should be cleaned in the internal switch E44 windshield.

20

Solution: Replace the steering wiper combination switch, troubleshooting.

Case 6

Failure phenomenon: a 2009 production of 1.6 L Sunny sedan with automatic transmission, mileage is 13,000 km. Users reflect the remote control does not open and close the door.

Check Analysis: by maintenance personnel at the remote control unlocking and locking the push button, and the normal luminance indicator blinks, indicating that the battery in the remote power sufficient. Open and close the door with a key, central locking response. VAS5052 connected fault diagnostic, self-diagnostic function selected options into the BCM control unit, measuring data query block 015 sets a region. Pressing the remote control button, the operation is not the measured value is always displayed, indicating that the control unit does not recognize the radio signal to the remote controller, it seems necessary to re-match the remote control.

Troubleshooting: selecting matching option, into the channel 15 to factory setting Now 0. 00 into the channel, clear learning value, enter the 01-channel remote control key settings, press the remote control click Save any key, left and right turn signal on the instrument flashes to indicate a successful match. Read Block 015 sets a measurement area, the display may be identified in the radio signal of the remote control open and close. Remote control door opening and closing function recovery, troubleshooting.

(The End)

(Chenzhong Ze)

Leave a Reply

Your email address will not be published. Required fields are marked *