LEXUS Link System: Pre-Check

PRECAUTION
1. A GPS antenna for the Mayday system is installed near the rear speakers. Therefore, attaching a metallic film to the rear glass or setting any object close to the rear speakers prevents the position data from being received properly.
2. If the ignition switch is turned ON with the AIRBAG ECU connectors disconnected, or if a vehicle battery is removed with the ignition switch ON or if the +B circuit is OPEN within 10 sec. after the ignition switch is turned OFF, the system will determine this condition as a failure and it will automatically call the call center.
  To prevent this, perform the following when working on operation related to the AIRBAG ECU or a battery:
  - Disconnect the connectors of the Mayday ECU and the backup battery before disconnecting the AIRBAG ECU connector. (Disconnect the connectors of the vehicle harness and the Mayday assembly.)
  - Be sure that the ignition switch is OFF when removing a vehicle battery.
  NOTE:
  - When an accidental call is made automatically, access to the call center and ask them to cut off the line.
  - If no signal has been received from the AIRBAG ECU since the ignition switch was turned ON, a service call will be made.
  - If good signal reception from the AIRBAG ECU after the ignition switch ON is interrupted, an emergency call will be made.
3. When the life of the back-up battery becomes short, the voltage gets down and at this time Mayday ECU detects "DTC5". In this case, proceed troubleshooting by following "DTC5".
DIAGNOSIS SYSTEM
When a system error is detected, the Mayday system will inform the driver of the error by providing the following voice warning: "A LEXUS Link System error has been detected. Please contact your LEXUS dealer." Also, in the case below, it will make a service call to the call center.
- While the ignition switch is ON, the Mayday ECU cannot receive BEAN signal from the AIRBAG ECU.
- While the ignition switch is ON, power is not supplied from a vehicle battery.
DTC CHECK
Repeatedly turning ON and OFF the ignition switch 3 times within 15 sec. while pressing "PLAY" or "VOLUME+" allows the system to enter the diagnosis mode. In this mode, diagnosis result is informed by a voice. Refer to DIAGNOSIS TROUBLE CODE CHART for DTC details.
DTC CLEARANCE
DTC will be cleared when the trouble is recovered normally.

LEXUS LINK SYSTEM INFRASTRUCTURE TROUBLESHOOTING

Item

Symptom

Cause

Countermeasure Method

Check Method

Activate

Impossible to activate

Infrastructure/transceiver

Is phone connected to the center by pressing service button?
Yes: Problem in center/infrastructure
No: Problem in radio/infrastructure --> If transceiver. is with in SSC target range, replace

Problem in center/infrastructure
1. --> Inform to TMS and ask it to be repaired via company.
Problem in transceiver.
1. --> Replace transceiver.
In some cases, by making the vehicle run (⁽¹⁾) to change the cover area of the cellular, the service connection may be able to the activated even in the area where the problem occurred.

Service call
Emergency call

Impossible to connect to the center
Connection retry frequently occurs

Infrastructure

Run the vehicle at least dozens of miles (⁽¹⁾), inspect that the connectivity is in relation to the place or the area. If it is not in relation to the place or area, the problem must be in ECU or antenna. If it is in relation to the place or area, the problem must be in infrastructure.

If the problem is not infrastructure, check the wiring connection of antenna and antenna cable. If the connection has no problem, check the Mayday ECU and transceiver.

Impossible to connect to the center and the message to request to input the number of credit card comes out.

Infrastructure

Set up of infrastructure is wrong.

The cellular carrier in the area does not set up to accept MIN No. for the transceiver on the vehicle.
--> Inform to TMS to ask the set up via company.

Disconnection immediately after the connection

Infrastructure/transceiver

Run the vehicle at least dozens of miles (⁽¹⁾), inspect that the connectivity is in relation to the place or the area.
If it is not in relation to the place or area, the problem must be in ECU or antenna. If it is in relation to the place or area, the problem must be in infrastructure.

Unless the problem in the infrastructure, check the wiring connection of antenna and antenna cable. If these has no problem, check Mayday ECU and transceiver.

After moving far away from the previous place, connection become difficult.

Infrastructure

As the initial registration information when activation is different from the assumed information in the present area, continuity becomes worse.

Inform to the center by service call and ask to change the registration and perform down load of the set up information again.

The system has no response after the following message. "Calling the LEXUS Link Center" or "Placing an emergency call to LEXUS Link Center".

Infrastructure

According to the cellular electronic wave condition in the area, this problem may occur. As the vehicle data reaches the center, the center will call back to the vehicle.

Communication quality is bad.

Infrastructure

Run the vehicle at least dozen of miles (⁽¹⁾), inspect that the connectivity is in relation to the place or the area. If it is not in relation to the place or area, the problem must be in infrastructure.

Unless the problem is infrastructure, check the vehicle equipment such as mike, etc.

⁽¹⁾	Regarding the vehicle running distance and the area, these are to be until just out of the cover area of the concerned cellular area.