Bosch Tech 2 User Manual

Te c h  2Page 6-1
6.  TROUBLESHOOTING
This section is a general troubleshooting guide for all vehicle applications of the Tech 2 scan tool. Some of 
the information may differ for your particular vehicle application. 
When the Tech 2 appears to be operating abnormally, refer to this section for probable causes and solutions.
The following two types of self tests are available on the Tech 2: 
• Power On Self Test (POST) :checks the major functions of the Tech 2 at power-up. 
• Self Tests :check the major...

Troubleshooting
Page 6-2Te c h  2
• Real-time clock 
• Keypad controller and keypad 
• Main UART (Universal Asynchronous Receiver/Transmitter) 
Results of POST may include fatal errors that do not allow you to continue, or non-fatal errors that allow 
you to continue without full Tech 2 operation. If normal Tech 2 functions are stopped or limited, contact 
Customer Support to determine if service is required. 
At completion of POST, the following audible signals indicate a pass or fail 
condition: 
• One...

Troubleshooting
Te c h  2Page 6-3
FIGURE 6-1. Tech 2 Start-Up Screen
FIGURE 6-2. Tools Options Selected on Main Menu 

Troubleshooting
Page 6-4Te c h  2
TECH 2 SELF TEST MAIN MENU 
Each Tech 2 Self Test main menu selection is explained in detail on the following pages. All users have 
access to all the options listed (see Figure 6-5). Read all screen instructions and connect or disconnect the 
appropriate cables and loopback adapters. Screen messages display when external loopback connectors are 
connected. For specific loopback connection information, refer to Figure 3-2, Figure 3-4, and Figure 6-4. 
F0: Automated Main...

Troubleshooting
Te c h  2Page 6-5
The Automated Main PCB portion tests the following components: 
•RAM / ROM 
• RS-485 loopback 
*
• RS-232 loopback *
• Keypad 
• PCMCIA slot 1 
*. Each of these tests requires the conenction of a loopback adapter to the Tech 2.
FIGURE 6-4. Connection of DLC Loopback Adapter to the Tech 2 VCI ConnectorTech 2 VCI connector 
DLC loopback adapter
(P/N 02002953) 
FIGURE 6-5. Tech Automated Main PCB and VCI Test Selected on Tech 2 
Self Test Main Menu 

Troubleshooting
Page 6-6Te c h  2
• PCMCIA slot 2 
• Display controller 
• Sound transducer 
• Real-time clock 
Refer to Ta b l e 6 - 1 and Ta b l e 6 - 2 for help in diagnosing problems that involve the Tech 2s PCB and VCI. 
If the Tech 2 passes all Automated Main PCB and VCI tests, you do not need to run any more tests to verify 
that the Tech 2 is working properly.
The following test results are displayed: 
Once tests are complete, select the soft keys Main Details or VCI Details (Figure 6-6) to...

Troubleshooting
Te c h  2Page 6-7
 
FIGURE 6-7. Main Details Selection
FIGURE 6-8. VCI Details Selection 

Troubleshooting
Page 6-8Te c h  2
TestResultsSolution
RAM/ROM 0-Pass
1-ROM read fail
2-RAM read fail
3-RAM write and read do not compareRecord type of failure.
Cycle Tech 2 power (press [PWR]) and retest.
If problem persists, contact Customer Support.
RS-485 loopback Pass
Fail-Loopback may not be connectedCheck loopback connection.
If problem persists, contact Customer Support.
RS-232 loopback Pass
Fail-Loopback may not be connectedCheck loopback connection.
If problem persists, contact Customer...

Troubleshooting
Te c h  2Page 6-9
SIPO (Serial In 
Parallel Out) Pass/fail for each area tested If a failure occurs, cycle Tech 2 and retest. 
If problem persists, contact Customer Support.
DLC 
(Data Link 
Connector)DLC1 - DLC2
pass/fail count 
DLC2 - DLC1
pass/fail countIf a failure occurs, cycle Tech 2 and retest. 
If problem persists, contact Customer Support.
CCD 
(Chrysler Collision 
Detection)CCD - pass/fail 
CCD - loopback not connected Connect loopback and retest if loopback not 
connected. 
If...

Troubleshooting
Page 6-10Te c h  2
F1: Automated Main PCB Test 
This test works the same as the Automated Main PCB and VCI test, except the VCI portion of the test is not 
included (Figure 6-9). 
VCI TPU (Time 
Processor Unit) TPU0 - pass/fail 
TPU1 - pass/fail 
TPU5 - pass/fail 
TPU12 & TPU15 - pass/fail (or not 
tested if no loopback) 
TPU13 & TPU14 - pass/fail (or not 
tested if no loopback)For any failure, cycle Tech 2 and retest. 
If problem persists, contact Customer Support.
VCI level shifters...