Front
FRONT WIPER AND WASHER SYSTEMSystem Description
- All front wiper relays (HI, LO) are included in IPDM E/R (intelligent power distribution module engine room).
- Wiper switch (combination switch) is composed of a combination of 5 output terminals and 5 input terminals. Terminal combination status is read by BCM (body control module) when switch is turned ON.
- BCM controls front wiper LO, HI, and INT (intermittent) operation.
- IPDM E/R operates wiper motor according to CAN communication signals from BCM.
OUT LINE
Power is supplied at all times
- through 50 A fusible link (letter M, located in fuse, fusible link and relay box.)
- to BCM terminal 55,
- through 15 A fuse [No. 22, located in fuse block (J/B)]
- to BCM terminal 42,
- through 30 A fuse (No. 73, located in IPDM E/R)
- to front wiper relay, located in IPDM E/R,
- through 15 A fuse (No. 78, located in IPDM E/R) and
- through 10 A fuse (No. 71, located in IPDM E/R)
- to CPU located in IPDM E/R.
When the ignition switch is ON or START position, power is supplied
- to ignition relay located in IPDM E/R, from battery direct,
- through 15 A fuse [No. 1, located in fuse block (J/B)]
- to BCM terminal 38,
- through ignition relay, located in IPDM E/R
- to front wiper relay, located in IPDM E/R
- to front wiper high relay, located in IPDM E/R and
- to CPU located in IPDM E/R,
- through 10 A fuse (No. 84, located in IPDM E/R)
- through IPDM E/R terminal 44
- to combination switch terminal 14.
Ground is supplied
- to BCM terminals 49 and 52
- through grounds M35, M45 and M85,
- to IPDM E/R terminals 38 and 60
- through grounds E21, E50 and E51,
- to combination switch terminal 12
- through grounds M35, M45 and M85.
LOW SPEED WIPER OPERATION
When wiper switch is in LOW position, BCM detects low speed wiper ON signal by BCM wiper switch reading function.
BCM sends front wiper request signal (LO) through CAN communication
- from BCM terminals 39 and 40
- to IPDM E/R terminals 48 and 49.
When IPDM E/R receives front wiper request signal (LO), it turns ON front wiper relay located in IPDM E/R, power is supplied
- through front wiper relay
- through front wiper high relay
- through IPDM E/R terminal 21
- to front wiper motor terminal 1.
Ground is supplied
- to front wiper motor terminal 2
- through grounds E21, E50 and E51.
With power and ground supplied, the front wiper motor operates at low speed.
HIGH SPEED WIPER OPERATION
When wiper switch is in HI position, BCM detects high speed wiper ON signal by BCM wiper switch reading function.
BCM sends front wiper request signal (HI) through CAN communication
- from BCM terminals 39 and 40
- to IPDM E/R terminals 48 and 49.
When IPDM E/R receives front wiper request signal (HI), it turns ON front wiper relay (located in IPDM E/R),
power is supplied
- through front wiper relay
- through front wiper high relay
- through IPDM E/R terminal 31
- to front wiper motor terminal 4.
Ground is supplied
- to front wiper motor terminal 2
- through grounds E21, E50 and E51.
With power and ground supplied, the front wiper motor operates at high speed.
INTERMITTENT OPERATION
Front wiper intermittent operation delay interval is determined from a combination of 3 switches (intermittent operation dial position 1, 2, and 3) and vehicle speed signal.
Speed dependent wiper controlled mode can be changed by the function setting of CONSULT-II or display.
During each intermittent operation delay interval, BCM sends front wiper request signal to IPDM E/R.
Wiper Dial Position Setting
Example: For wiper intermittent dial position 1
Using combination switch reading function, BCM detects ON/OFF status of INT VOLUME 1, 2, and 3.
When combination switch status is as listed here, BCM determines that it is wiper intermittent dial position 1.
- INT VOLUME 1: ON (Continuity exists between combination switch output 3 and input 1.)
- INT VOLUME 2: ON (Continuity exists between combination switch output 5 and input 1.)
- INT VOLUME 3: ON (Continuity exists between combination switch output 4 and input 2.)
BCM determines front wiper intermittent operation delay interval from wiper intermittent dial position 1 and vehicle speed, and sends wiper request signal (INT) to IPDM E/R.
AUTO STOP OPERATION
With wiper switch turned OFF, wiper motor will continue to operate until wiper arms reach windshield base.
When wiper arms are not located at base of windshield with wiper switch OFF, ground is provided
- from IPDM E/R terminal 21
- to front wiper motor terminal 1, in order to continue wiper motor operation at low speed.
When wiper arms reach base of windshield, front wiper motor terminals 5 and 2 are connected, and Ground is supplied
- to IPDM E/R terminal 32
- through front wiper motor terminals 5 and 2
- through grounds E21, E50 and E51.
Then the IPDM E/R sends auto stop operation signal to BCM through CAN communication.
When the BCM receives auto-stop operation signal, BCM sends wiper stop signal to IPDM E/R through CAN communication.
IPDM E/R stops wiper motor. Wiper motor will then stop wiper arms at the STOP position.
WASHER OPERATION
When wiper switch is in front wiper washer position with ignition switch on, BCM detects front wiper switch is on the washer position by BCM wiper switch reading function (Refer to "COMBINATION SWITCH READING FUNCTION" in Wiper and Washer System), combination switch (wiper switch) ground is supplied
- to combination switch terminal 13
- through front and rear washer pump terminal 1
- to front and rear washer pump terminal 2
- through combination switch terminal 11
- to combination switch terminal 12
- through grounds M35, M45 and M85.
With ground supplied, front and rear washer pump is operated.
When BCM detects that front and rear washer pump has operated for 0.4 seconds or linger, BCM operates front wiper motor for low speed.
When BCM detects washer switch is OFF, low speed operation cycles approximately 2 times and stops.
MIST OPERATION
When wiper switch is turned to MIST position, wiper low speed operation cycles once and then stops. For additional information about wiper operation under this condition, Refer to "LOW SPEED WIPER OPERATION".
If switch is held in MIST position, low speed operation continues.
FAIL-SAFE FUNCTION
If an abnormality occurs in CAN communications, IPDM E/R holds the condition just before fail-safe status is initiated until ignition switch is turned OFF. (If wipers were operating in LO just before the initiation of fail-safe status, they continue to operate in LO until ignition switch is turned OFF.)
COMBINATION SWITCH READING FUNCTION
Description
- BCM reads combination switch (wiper) status, and controls related systems such as head lamps and wipers, according to the results.
- BCM reads information of a maximum of 20 switches by combining five output terminals (OUTPUT 1-5) and five input terminals (INPUT 1-5).
Operation Description
- BCM activates transistors of output terminals (OUTPUT 1-5) periodically and, and allows current to flow in turn.
- If any (1 or more) switches are turned ON, circuit of output terminals (OUTPUT 1-5) and input terminals (INPUT 1-5) becomes active.
- At this time, transistors of output terminals (OUTPUT 1-5) are activated to allow current to flow. When voltage of input terminals (INPUT 1-5) corresponding to that switch changes, interface in BCM detects voltage change, and BCM determines that switch is ON.
BCM - Operation Table of Combination Switches
BCM reads operation status of combination switch using combinations shown in table.
Sample Operation: (When Wiper Switch Turned to LOW Position)
- When wiper switch is turned to LOW position, front wiper LOW contact in combination switch turns ON. At this time if OUTPUT 1 transistor is activated, BCM detects that voltage changes in INPUT 3.
- When BCM detects that voltage changes in INPUT 3 while OUTPUT 1 transistor is ON, it judges that front wiper switch is in LOW position. Then BCM sends front wiper request signal (LO) to IPDM E/R using CAN communication.
- If BCM detects that voltage changes in INPUT 3 when OUTPUT 1 transistor is activated again, it recognizes that wiper switch is still in LOW position.
NOTE: Each OUTPUT terminal transistor is activated at 10 ms intervals. Therefore after switch is turned ON, electrical loads are activated with time delay. But this time delay is so short that it cannot be detected by human senses.
Operation Mode
Combination switch reading function has operation modes shown here.
1. Normal status
- When BCM is not in sleep status, OUTPUT terminals (1-5) each turn ON-OFF every 10 ms.
2. Sleep status
- When BCM is in sleep status, transistors of OUTPUT 1 and 5 stop the output, and BCM enters low power mode. Mean while OUTPUT 2, 3, and 4 send out ON signal every 60 ms, and accept input from lighting switch system.
CAN Communication System Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-board multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
CAN Communication Unit
Refer to "CAN System Specification Chart".