Part 6 of 7
OVERDRIVE OFF INDICATORAn overdrive off indicator is standard equipment on all instrument clusters. However, on vehicles not equipped with the optional overdrive automatic transmission, this indicator is electronically disabled. The overdrive off indicator consists of the text "O/D OFF", which appears in the lower portion of the electronic gear selector indicator Vacuum Fluorescent Display (VFD). The VFD is part of the cluster electronic circuit board, and is visible through a cutout located in the lower right corner of the cluster overlay. The dark lens of the VFD prevents the indicator from being clearly visible when it is not illuminated. The text "O/D OFF" appears in an amber color and at the same lighting level as the gear selector indicator information when it is illuminated by the instrument cluster electronic circuit board. The overdrive off indicator is serviced as a unit with the VFD in the instrument cluster.
The overdrive off indicator gives an indication to the vehicle operator when the OFF position of the overdrive OFF switch has been selected, disabling the electronically controlled overdrive feature of the automatic transmission. This indicator is controlled by the instrument cluster circuit board based upon cluster programming and electronic messages received by the cluster from the Powertrain Control Module (PCM) over the Chrysler Collision Detection (CCD) data bus. The overdrive off indicator receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (run-start) circuit whenever the ignition switch is in the ON or Start positions; therefore, the indicator will always be OFF when the ignition switch is in any position except ON or Start. The indicator only illuminates when it is switched to ground by the instrument cluster circuitry. The instrument cluster will turn ON the overdrive off indicator for the following reasons:
- Bulb Test - Each time the ignition switch is turned to the ON position the overdrive off indicator is illuminated for about two seconds as a bulb test.
- Overdrive OFF Lamp-ON Message - Each time the cluster receives an overdrive off lamp-ON message from the PCM indicating that the OFF position of the overdrive off switch has been selected, the overdrive off indicator will be illuminated. The indicator remains illuminated until the cluster receives an overdrive off lamp-OFF message from the PCM, or until the ignition switch is turned to the OFF position, whichever occurs first.
- Actuator Test - Each time the cluster is put through the actuator test, the overdrive off indicator will be turned ON, then OFF again during the VFD portion of the test to confirm the functionality of the VFD, and again during the bulb check portion of the test to confirm the functionality of the cluster control circuitry.
The PCM continually monitors the overdrive OFF switch to determine the proper outputs to the automatic transmission. The PCM then sends the proper overdrive off lamp-ON and lamp-OFF messages to the instrument cluster. For further diagnosis of the overdrive off indicator or the instrument cluster circuitry that controls the indicator, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). For proper diagnosis of the overdrive control system, the PCM, the CCD data bus, or the message inputs to the instrument cluster that control the overdrive off indicator, a DRB III scan tool is required. Refer to the appropriate diagnostic information.
SEATBELT INDICATOR
A seatbelt indicator is standard equipment on all instrument clusters. The seatbelt indicator is located near the lower edge of the instrument cluster overlay, to the right of center. The seatbelt indicator consists of a stencil-like cutout of the International Control and Display Symbol icon for "Seat Belt" in the opaque layer of the instrument cluster overlay. The dark outer layer of the overlay prevents the indicator from being clearly visible when it is not illuminated. A red lens behind the cutout in the opaque layer of the overlay causes the icon to appear in red through the translucent outer layer of the overlay when the indicator is illuminated from behind by a Light Emitting Diode (LED) soldered onto the instrument cluster electronic circuit board. The seatbelt indicator is serviced as a unit with the instrument cluster.
The seatbelt indicator gives an indication to the vehicle operator of the status of the driver side front seatbelt. This indicator is controlled by a transistor on the instrument cluster circuit board based upon cluster programming and a hard wired input from the seatbelt switch in the driver side front seatbelt retractor through the seat belt indicator driver circuit. The seatbelt indicator Light Emitting Diode (LED) receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (run-start) circuit whenever the ignition switch is in the ON or Start positions; therefore, the indicator will always be OFF when the ignition switch is in any position except ON or Start. The LED only illuminates when it is provided a path to ground by the instrument cluster transistor. The instrument cluster will turn ON the seatbelt indicator for the following reasons:
- Seatbelt Reminder Function - Each time the cluster receives a battery current input on the fused ignition switch output (run-start) circuit, the indicator will be illuminated as a seatbelt reminder for about seven seconds, or until the ignition switch is turned to the OFF position, whichever occurs first. This reminder function will occur regardless of the status of the seatbelt switch input to the cluster.
- Driver Side Front Seatbelt Not Buckled - Following the seatbelt reminder function, each time the cluster detects an open circuit on the seat belt indicator driver circuit (seatbelt switch open - seat- belt unbuckled) with the ignition switch in the Start or ON positions, the indicator will be illuminated. The seatbelt indicator remains illuminated until the seat belt indicator driver input to the cluster is closed to ground (seatbelt switch closed - seatbelt buckled), or until the ignition switch is turned to the OFF position, whichever occurs first.
- Actuator Test - Each time the cluster is put through the actuator test, the indicator will be turned ON, then OFF again during the bulb check portion of the test to confirm the functionality of the LED and the cluster control circuitry.
The seatbelt switch input to the instrument cluster circuitry can be diagnosed using conventional diagnostic tools and methods. For further diagnosis of the seatbelt indicator or the instrument cluster circuitry that controls the LED, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING).
SECURITY INDICATOR
A security indicator is standard equipment on all instrument clusters. However, on vehicles not equipped with the optional Vehicle Theft Security System (VTSS), this indicator is mechanically disabled. The security indicator is located near the lower edge of the instrument cluster overlay, to the right of center. The security indicator consists of a stencil-like cutout of the word "SECURITY" in the opaque layer of the instrument cluster overlay. The dark outer layer of the overlay prevents the indicator from being clearly visible when it is not illuminated. A red lens behind the cutout in the opaque layer of the overlay causes the "SECURITY"' text to appear in red through the translucent outer layer of the overlay when it is illuminated from behind by a Light Emitting Diode (LED) soldered onto the instrument cluster electronic circuit board. The security indicator is serviced as a unit with the instrument cluster.
The security indicator gives an indication to the vehicle operator when the Vehicle Theft Security System (VTSS) is arming or is armed. This indicator is controlled by a hard wired input to the instrument cluster from the Central Timer Module (CTM) on the VTSS indicator driver circuit. The security indicator Light Emitting Diode (LED) receives battery current on the instrument cluster electronic circuit board at all times through a non-switched fused B(+) circuit; therefore, the LED will remain functional regardless of the ignition switch position. The LED only illuminates when it is provided a path to ground by the [1][2]CTM. The security indicator will be illuminated for the following reasons:
- VTSS Indication - During the seventeen second VTSS arming function, the [1][2]CTM will flash the security indicator ON and OFF repeatedly at a steady, fast rate to indicate that the VTSS is in the process of arming. Following successful VTSS arming, the CTM flashes the security indicator ON and OFF continuously at a slower rate to indicate that the VTSS is armed. The security indicator continues flashing at the slower rate until the VTSS is disarmed or triggered. If the VTSS alarm is triggered, the CTM will flash the security indicator at a steady, fast rate for up to eighteen minutes or until the triggering condition is removed, before returning to the slower, armed flash rate.
- Actuator Test - Each time the instrument cluster is put through the actuator test, the security indicator will be turned ON, then OFF again during the bulb check portion of the test to confirm the functionality of the LED and the cluster control circuitry.
The [1][2]CTM provides a hard wired ground input to the instrument cluster circuitry through the VTSS indicator driver circuit whenever the ignition switch is in the Off position and the VTSS is arming, armed, or triggered. For further diagnosis of the security indicator or the instrument cluster circuitry that controls the indicator, (Refer to INSTRUMENT CLUSTER - DIAGNOSIS AND TESTING). The VTSS indicator driver circuit input to the instrument cluster can be diagnosed using conventional diagnostic tools and methods. For proper diagnosis of the VTSS or the CTM, a DRB III scan tool is required. Refer to the appropriate diagnostic information.