How to Use Land Rover Testbook Scan Tool

The Land Rover TestBook Scan Tool provides complete diagnostics for GEMS equipped vehicles. Data is obtained through the 16-pin OBD II Data Link Connector (DLC) located in the passenger compartment, in the passenger-side footwell.

The TestBook Scan Tool communicates through a special VSCI interface cable, known as the Test Brick.





Connect the TestBook to vehicle in the following manner:

Following the example shown in image, select the correct diagnostic cables for an OBD II application. Be sure that the cables are inserted into Socket 1 at the rear of the TestBook and are securely connected.

NOTE: The switchable TestBook lead (if available) may be interchanged with the GEMS TestBook lead (Blue Connector) for GEMS TestBook testing.





Once connected; Select the "GEMS NAS Only" icon from the main menu.





From this menu you are given the following Options:

- Diagnose Faults
- Input Monitors
- Output Drive
- Subsystem Tests

Diagnose Faults

This selection automatically runs a self-test and retrieves all system faults.

Fault Codes and explanations are provided on the touchscreen. Step-by-step diagnostic routines are provided on the TestBook. An integral DVOM and amp meter are provided for diagnostic use. By following the TestBook screens and providing responses to the on-screen questions, you will be able to pinpoint the source of the vehicle concern.

TestBook will also take you through a complete verification process once you have identified and fixed the concern to ensure that the vehicle is operating properly. Be sure to address all DTC's when performing TestBook Diagnostics.





Real Time Monitoring (Input Monitoring)

This selection allows you to examine the signals produced by each of the GEMS inputs.





Selecting the "O2 Front Sensor Voltages" icon on the TestBook screen moves you to a screen where Front Oxygen Sensor information is provided and continually updated.

Text provided on each screen provides you with background information on the signal and its function. Input monitoring allows you to use your knowledge of the GEMS Engine Management System and verify sensor operation.





Output Drive

This selection allows you to activate selected GEMS Outputs for audible or visual verification.

These actions can help you quickly pinpoint the source of a customer concern and is also useful when verifying system repairs.





Subsystem Tests

Subsystem tests follow programmed diagnostic paths for individual engine management systems or components.

These tests are similar to the guided diagnostics that are used when a system fault is present, but with an important difference.

These "mini health checks" can be performed whether or not the system has registered a fault, and can be used to verify a repair, or search for an intermittent fault. Note that the fault must be present at the time of testing.

It is also possible to mislead these tests into a misdiagnosis by responding to certain questions and/or prompts with inaccurate information.