Bosch Tech 2 User Manual

							Troubleshooting
Te c h  2Page 6-11
F2: Automated VCI Test 
This test works the same as the Automated Main PCB and VCI test, except the PCB portion of the test is not 
included (Figure 6-10). 
FIGURE 6-10. Automated VCI Test Selected on Tech 2 Self Test Main Menu 
						

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Page 6-12Te c h  2
F3: Selectable Main PCB Test 
Select F3: Selectable Main PCB (Figure 6-11) after a fail message has been displayed during the 
Automated Main PCB and VCI or Automated Main PCB tests. When you select F3: Selectable Main PCB, 
a screen like the one shown in Figure 6-12 is displayed. You may then select individual tests for failed 
components. For specific information on failed components, refer to the Main Printed Circuit Board (PCB) 
Diagnostic Chart (Ta b l e 6 - 1 ,  PCB Diagnostic Chart, on page 6-8). 
FIGURE 6-11. Selectable Main PCB Test Selected on Tech 2 Self Test Main Menu
FIGURE 6-12. Selectable Main PCB Self Test Screen 
						

							Troubleshooting
Te c h  2Page 6-13
F4: Selectable VCI Test 
Select F4: Selectable VCI (Figure 6-13) after a fail message displays during the Automated Main PCB and 
VCI or Automated VCI tests. When you select F4: Selectable VCI, a screen like the one shown in Figure 6-
14 is displayed. You may select individual tests for failed components from this screen. If you select More 
Tests, a screen like the one shown in Figure 6-15 is displayed. If you then select Previous Menu, the screen 
shown in Figure 6-14 returns. For specific information on failed components, refer to the Vehicle 
Communications Interface (VCI) Module Diagnostic Chart (Ta b l e 6 - 2 ,  VCI Module Diagnostic Chart, on 
page 6-8). 
FIGURE 6-13. Selectable VCI Test Selected on Tech 2 Self Test Main Menu
FIGURE 6-14. First Selectable VCI Self Test Screen 
						

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Page 6-14Te c h  2
 
FIGURE 6-15. Second Selectable VCI Self Test Screen 
						

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Te c h  2Page 6-15
F5: Power On Self Test Results 
Select F5: Power On Self Test Results (Figure 6-16) after a fail message displays during the Power On 
Self Test (POST). Specific information on the failure displays on the screen. Select F0, F1, F2, F3, or F4 to 
further isolate the specific fault. 
FIGURE 6-16. Power On Self Test Results Selected on Tech 2 Self Test Main Menu 
						

							Troubleshooting
Page 6-16Te c h  2
NO POWER TO TECH 2 
TROUBLESHOOTING TABLES 
Use the following tables to diagnose, isolate, and correct power source problems that may cause a No Power 
condition to your Tech 2 scan tool. 
To help determine the power supply source, see Chapter 4. 
Power Source: DLC Cable
Ste pActionYe sNo
1 Does vehicle support power through 
DLC cable connection exclusively? (If 
you are not sure, consult your service 
manual.) Go to Step 2. Use alternate power.
2 • Using a digital multi-meter (DMM), 
verify vehicle battery voltage. 
Is battery fully charged? Go to Step 3.  Charge battery.
3 • Verify connection at vehicle DLC 
connector for loose or damaged pin(s). 
Did you find a problem?Repair connector.
(Consult vehicle service manual.) Go to Step 4. 
4 • Disconnect DLC cable from vehicle. 
• Power on Tech 2 using alternate 
power source at DLC cable power jack 
connection. 
Did your Tech 2 power on? Problem with vehicle. 
(Consult vehicle service manual.)Go to Step 5. 
5 • Remove DLC cable from Tech 2 and 
attach alternate power supply at VCI 
power jack connection located at the 
bottom of Tech 2. 
Does Tech 2 power on?Replace DLC cable.  Problem with Tech 2. 
Contact Customer 
Support.
TABLE 6-3.  DLC Cable No Power Troubleshooting Table 
						

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Te c h  2Page 6-17
Power Source: Cigarette Lighter Power Cable
StepActionYe sNo
1 • Unplug cigarette lighter power cable 
from DLC cable. 
• Using a digital multi-meter (DMM), 
verify voltage output at cigarette 
lighter power cable power jack. 
Do you have battery voltage output? Go to Step 3.  Go to Step 2. 
2 • Check fuse in cigarette lighter power 
cable (refer to Figure 6-17). 
Does fuse need replacing? Replace fuse.  Go to step 3.
3 • Remove DLC cable from Tech 2. 
• Plug in cigarette lighter power jack to 
the VCI power jack connector located 
at bottom of Tech 2. 
Does the Tech 2 power on? Replace DLC cable. Problem with Tech 2.
Contact Customer 
Support.
4 • Using a DMM, verify voltage output 
at battery. 
Do you have battery voltage output? Go to Step 5. Charge battery.
5 • Disconnect cigarette lighter power 
cable from vehicle and verify voltage 
output at vehicle cigarette lighter 
socket. 
Do you have battery voltage output? Replace cigarette lighter power 
cable. Problem with vehicle. 
Consult vehicle 
service manual.
TABLE 6-4.  Cigarette Lighter Power Cable No Power Troubleshooting Table 
						

							Troubleshooting
Page 6-18Te c h  2
Power Source: Battery Power Cable
Ste pActionYe sNo
1 • Unplug battery power cable power 
jack from DLC cable. 
• Using a digital multi-meter (DMM), 
verify voltage output at battery power 
cable power jack. 
Do you have battery voltage output?Go to Step 3.  Go to Step 2. 
2 • Check fuse(s) in battery power cable 
(refer to Figure 6-18). 
Does fuse(s) need replacing? Replace fuse(s).  Go to Step 3.
3 • Remove DLC cable from Tech 2. 
• Plug in battery power cable power 
jack to the VCI power jack connector 
located at bottom of Tech 2. 
Does the Tech 2 power on? Replace DLC cable.  Problem with Tech 2. 
Contact Customer 
Support.
4 • Using a DMM, verify voltage output 
at battery. 
Do you have battery voltage output?Replace battery power cable. Charge battery. 
TABLE 6-5.  Battery Power Cable No Power Troubleshooting Table
Power Source: Battery Power Cable
Ste pActionYe sNo
1 • Unplug NAO (or Universal) power 
supply power jack from DLC cable. 
• Using a digital multi-meter (DMM), 
verify voltage output at power jack. 
Do you have battery voltage output?Go to Step 2.  Replace NAO or 
Universal power 
supply. 
2 • Remove DLC cable from Tech 2. 
• Plug in NAO (or Universal) power 
supply power jack to the VCI power 
jack connector located at bottom of 
Tech 2. 
Does the Tech 2 power on? 
 Replace DLC cable.  Problem with Tech 2. 
Contact Customer 
Support. 
TABLE 6-6.  NAO or Universal No Power Troubleshooting Table 
						

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Te c h  2Page 6-19
CIGARETTE LIGHTER POWER CABLE 
3-AMP FUSE REPLACEMENT 
A three-amp removable fuse is located in the cigarette lighter power cable (P/N 02002954) connector. 
When required, check or replace the fuse by performing the following steps: 
1. Ensure the cigarette lighter power cable is not connected to the vehicle or Tech 2.
2. Unscrew the fuse retainer cap and remove the 3-amp fuse. 
3. Inspect the fuse for damage and replace it with an identical 3-amp fuse if required. 
4. Verify by connecting the cigarette lighter power cable to the Tech 2 and vehicle.
FIGURE 6-17. Cigarette Lighter Power Cable 3-Amp Fuse ReplacementCigarette lighter power cable 
3-amp fuse 
Fuse retainer cap  
						

							Troubleshooting
Page 6-20Te c h  2
BATTERY POWER CABLE 3-AMP FUSE 
REPLACEMENT 
Two three-amp fuses are located in the battery power cable (P/N 02002956) three-amp fuse box. 
When required, check or replace the fuse(s) by following the steps below. 
 
1. Ensure the battery power cable is not connected to the vehicle battery or Tech 2. 
2. Use a standard fuse puller to remove the fuse(s) from the fuse box. 
3. Inspect the fuse(s) for damage and replace with identical 3-amp fuse(s) if required. 
4. Verify by connecting the battery power cable to the Tech 2 and vehicle battery. 
CAUTION
CAUTION!To help avoid personal injury by electric shock, make sure the battery 
power cable is not connected to the vehicle’s battery before removing the 
fuse(s).
FIGURE 6-18. Battery Power Cable 3-Amp Fuse ReplacementBattery power cable 
Battery clamps  3-amp fuse 3-amp fuse box