Part 2B
Active CodesThe code becomes active as soon as the malfunction is detected or key-in, whichever occurs first. An active trouble code indicates an on-going malfunction. This means that the defect is currently there every time the airbag control module checks that circuit or component. It is impossible to erase an active code. Active codes automatically erase by themselves when the reason for the code has been corrected. With the exception of the warning lamp trouble codes or malfunctions, when a malfunction is detected, the airbag lamp remains lit for a minimum of 12 seconds or as long as the malfunction is present.
Stored Codes
Airbag codes are automatically stored in the ORC's memory as soon as the malfunction is detected. The exception is the Loss of Ignition Run Only code which is an active code only. A stored code indicates there was an active code present at some time. However, the code currently may not be present as an active code, although another code could be active. When a trouble code occurs, the airbag warning indicator illuminates for 12 seconds minimum (even if the problem existed for less than 12 seconds). The code is stored, along with the time in minutes it was active, and the number of times the ignition has been cycled since the problem was last detected. The minimum time shown for any code will be one minute, even if the code was actually present for less than one minute. Thus, the time shown for a code that was present for two minutes 13 seconds, for example, would be three minutes. If a malfunction is detected a diagnostic trouble code is stored and will remain stored. When and if the malfunction ceases to exist, an ignition cycle count will be initiated for that code. If the ignition cycle count reaches 100 without a reoccurrence of the same malfunction, the diagnostic trouble code is erased and that ignition cycle counter is reset to zero. If the malfunction reoccurs before the count reaches 100, then the ignition cycle counter will be reset and the diagnostic trouble code will continue to be a stored code. If a malfunction is not active while performing a diagnostic test procedure, the active code diagnostic test will not locate the source of the problem. In this case, the stored code can indicate an area to inspect. It no obvious problems are found, erase stored codes, and with the ignition on wiggle the wire harness and connectors, rotate the steering wheel from stop to stop. Recheck for codes periodically as you work through the system. This procedure may uncover a malfunction that is difficult to locate.
AUDIO SYSTEM
All radio systems available on the 2001 JR communicate on the PCI Bus. They use the bus for three reasons. The first is to communicate trouble codes, second is to receive dimming information, and third is to receive cabin equalization information. The audio system is available in a 4 speaker base system and a 6 speaker system with an external power amplifier. An in-dash CD Changer is also optional. Depending on the manufacturer of the radio, some systems have a front/rear output system and others have a left/right output system.
When troubleshooting output shorts or "output" error messages, the following applies:
On radios without an external amplifier, the term output refers to the path between the radio and the speaker. This type of circuit can be monitored all the way through the speaker connections by the radio assembly. When the radio displays a shorted output DTC with this type of system, the speaker, radio, or wiring could be at fault. The output DTC could refer to a front or rear output or a left or right output. The reason for the difference is the pairing of the output sections of the radio. Some are paired left and right, others are paired front and rear.
On radios with an external amplifier, the term "output" refers to the circuit between the radio connector and the amplifier. The radio is capable of monitoring only this portion and can tell nothing about the circuit between the amplifier and the speakers. Consequently, a shorted output DTC on this type of system would only refer to this circuit. A faulty speaker could not cause this DTC.
The new in-dash CD-changer is designed to fit into the existing cubby bin in the center stack. This new cartridge-less CD-changer is controlled by your radio, and allows you to individually load up to four discs at one time. However, due to its compact design, the CD-changer can only carry out one operation at a time. For example you can not load a new disc while playing another at the same time. Each operation happens sequentially.
The radio unit installed with you system provides control over all features of the CD-changer with the exception of the CD load and eject functions, which are controlled by buttons located on the front of the CD-changer. The radio also supplies the power, ground, PCI Bus, left and right speaker output through a single DIN cable. All features you would expect, such as Disc Up/Down, Track Up/Down, Random and Scan are controlled by the radio, which also displays all relevant CD-changer information on the radio display.
The CD-changer contains a Load/Eject button and an indicator light for each of the four disc positions. The individual light indicates whether a CD is currently loaded in that particular chamber of the CD-changer. Pressing the individual Load/Eject button for a particular chamber will eject a disc currently present in that chamber. If the chamber is currently empty, actuating the Load/Eject button will position that chamber to receive and load a new disc in that chamber. BODY CONTROL MODULE
The body control module (BCM) supplies vehicle occupants with visual and audible information and controls various vehicle functions. To provide and receive information, the module is interfaced to the vehicle's serial bus communications network (the Programmable Communication Interface or PCI bus). This network consists of the powertrain control module (PCM), sentry key immobilizer module (SKIM), the Transmission Control Module (TCM), the electro/mechanical instrument cluster (MIC), Compass/mini-trip Computer (CMTC) occupant restraint control (ORC) module, optional Antilock Brakes (ABS), the radio remote CD-player, optional left and right airbag control modules. The (BCM) is operational when battery power is supplied to the module, ignition switch power is needed for ignition switched functions.
The body control module provides the following features:
A/C switch status/evaporator temperature status
BCM diagnostic support
Central lock and unlock (VTSS only)
Climate Control system support
Door ajar switch status
Door Lock Inhibit (key in ignition or headlamps/park lamps ON)
Electronic Odometer Support
Headlamp Time Delay
Illuminated Entry with "fade to OFF"
Interior lighting with battery save feature
Mechanical Instrument Cluster (fuel level, dim data, odometer & warning chime) support
Travel information system
Power convertible top
Power door lock multiplexing control
Rear Window Defogger Control
Remote Keyless Entry with Panic Mode
Remote power deck lid release
Rolling door lock control (customer programmable)
Sentry key immobilizer support
Vehicle Theft Security System
Wiper Control (speed sensitive with return to park)
The BCM receives information over the PCI Bus from the PCM in order to support certain features. The required information is as follows:
- Engine RPM
- Engine Temperature
- Injector on Time and Distance Pulses
- Vehicle Speed
- Charging System Failure, Engine Temperature Limp-In, VTSS Arming Status
- Engine Model
- "Check Engine" lamp status
The BCM provides the PCM with information on the A/C switch status and the VTSS status.
The JR has several customer programmable features which can be disabled or enabled by the customer.
CHIME SYSTEM
The chime system is comprised of an audible chime located internal to the BCM; and is dependent on various inputs to the BCM to operate. These inputs to the BCM include key-in ignition switch, exterior lamps as well as requests for the Mechanical Instrument Cluster from the seat belt switch input or whenever certain indicators are turned ON.
COMPASS/MINI-TRIP COMPUTER
The Compass/Mini-Trip Computer (CMTC) system is located between the center A/C ducts. The CMTC is an electronic control module with a vacuum fluorescent display (VFD) and two function switches. The CMTC is capable of displaying compass, temperature and trip computer information. Actuation of the STEP switch will cause the CMTC to change mode of operation while actuation of the US/M switch will toggle between English and Metric units. A reset of the trip computer is accomplished by pressing the STEP and US/M switches simultaneously.
The CMTC is active only when the ignition is on.
An "all segments" test can be performed by pressing both the "step" and "US/M" switches and then turning the ignition ON. The functions that are available via actuation of the STEP switch are as follows:
- Compass and ambient temperature
- Average Fuel Economy (AVE ECO)
- Distance To Empty (DTE)
- Present Fuel Economy (ECO)
- Trip odometer (ODO)
- Elapsed ignition time (ET)
- Blank screen (OFF)
Setting The Compass
The compass in the CMTC module is self-calibrating and requires no manual adjustment. If calibration is required, the word CAL will be displayed to indicate that the compass is in the fast calibrating mode. "CAL" will turn OFF after the calibration is completed. A manual calibration can be invoked by holding down the "step" and US/M buttons until the "CAL" lamp is lit.
Setting The Compass Variance
Variance is the difference between north and geographic north. To determine the variance for the area you are in, refer to the zone map below and follow the instructions provided. The number shown for your area is the variance number for your area.
1. With ignition ON, use the STEP button to select the Compass/Temperature display.
2. Press and hold the US/M and STEP buttons until VAR is displayed. CMTC displays the last variance zone and the word VAR. All other display segments are OFF.
3. Use the STEP button to select the proper variance zone number (1-15). Each variance zone represents a 4-degree shift in magnetic variation from central zone 8, which has no variation from true north.
4. After selecting the proper variance zone number, press the STEP and US/M buttons or wait several seconds. The new variance zone is then set and the CMTC will resume normal operation.
Ambient Temperature Sensor
The thermometer function is supported by the ambient temperature sensor, a wiring circuit, the Powertrain Control Module (PCM), the Programmable Communications Interface (PCI) data bus, and portion of the Compass Mini-Trip Computer (CMTC). If any portion of the ambient temperature sensor circuit fails, the BCM Will self-diagnose the circuit and set a DTC.
The CMTC Will lock the display at 54 °C (130 °F) if the sensor is exposed to temperatures above 54 ° (130 °F), or if the sensor is shorted. The CMTC Will lock the display at -40 °C (-40 °F) if the sensor is exposed to temperatures below -40 °C (-40 °F), or if the sensor circuit is open.
DOOR AJAR SYSTEM
The door ajar and decklid ajar states are used as inputs for the Body Control Module (BCM). The BCM uses these inputs to determine exactly what position the doors and decklid are in. The DRB III will display the state of the door ajar and the decklid ajar switches in Inputs/Outputs. It's important to note, that when any door, or the decklid is closed, the switch state on the DRB III will show OPEN. When any door, or the decklid is open the switch state on the DRB III will show CLOSED. During diagnosis, if a door or the decklid is closed and the DRB III displays the switch state as CLOSED, it indicates a shorted ajar circuit. If the door or the decklid is open and the DRB III displays the switch state as OPEN, it indicates an open ajar circuit.
EXTERIOR LIGHTING SYSTEM
Headlamp Delay
The headlamp time delay operates when the ignition switch is turned OFF while the headlamps are still ON, and the headlamps are then turned OFF within 45 seconds after the ignition is OFF. This will provide a 90-second time delay before turning OFF the headlamps.