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Home >> Suzuki >> 2004 >> Swift + >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (Data Link Communication System) >> Diagnostic Information and Procedures >> Scan Tool Does Not Communicate with Component >> Test Description
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Test Description

WARNING: This page is about a different car, the 2005 Suzuki Swift +, 2005 Pontiac Wave, and 2005 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

  1. 3:  This step checks whether the scan tool can communicate with other control modules on the vehicle. If the scan tool can communicate with one of the other modules then the DLC connector, the shared circuits, and the scan tool are OK.
  2. 4:  This step checks whether the ECM is receiving ignition positive voltage from the fuse F16 when the ignition is ON. The ECM cannot provide serial data without ignition positive voltage.
  3. 7:  This step checks for a high resistance or an open/short in the ECM serial data circuit.
  4. 8:  This step checks the ECM DLC Diagnostic circuit high resistance or open/short. This could cause the ECM not to communicate.
  5. 9:  This step checks to see if the EBCM is not communicating with the scan tool.
  6. 14:  This step checks to see if the SIR system is not communicating with the scan tool.
  7. 19:  This step checks to see if the theft deterrent-immobilizer system is not communicating with the scan tool.
Scan Tool Does Not Communicate with Component

Step Action Yes No
Schematic Reference:  Data Link Connector (DLC) Schematics  
1 Have you performed the Diagnostic System Check for the system in which the customer concern is apparent? Go to Step 2  Go to Diagnostic System Check - ABS in Antilock Brake System, or Diagnostic System Check - SIR in SIR, or Diagnostic Starting Point - Theft Deterrent in Theft Deterrent
2 Does the scan tool power up? Go to Step 3  Go to Scan Tool Does Not Power Up 
Does the scan tool communicate with the engine control module (ECM)? Go to Step 9  Go to Step 4 
With the ignition OFF:
  1. Disconnect the ECM connector.
  2. Turn ON the ignition.
  3. Test the ECM battery positive (B+) and/or ignition voltage circuits with a test lamp connected to ground.

Does the test lamp illuminate for all circuits?
Go to Step 5  Go to Step 24 
5 With the ECM still disconnected, test the ECM ground circuits with a test lamp connected to B+.
Does the test lamp illuminate for all ground circuits?
Go to Step 6  Go to Step 24 
6
  1. Reconnect the ECM connector.
  2. Connect the scan tool.
  3. Turn ON the ignition, with the engine OFF.
Does the scan tool display serial data?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 7 
Test the serial data circuit for an open, high resistance, or a short circuit. Refer to Circuit Testing in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 8 
Test the DLC diagnostic circuit for an open, high resistance or a short circuit. Refer to Circuit Testing in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 25 
Does the scan tool communicate with the EBCM? Go to Step 14  Go to Step 10 
10 Test the EBCM battery positive (B+) and/or ignition voltage circuits with a test lamp to ground.
Does the test lamp illuminate for all circuits?
Go to Step 11  Go to Step 24 
11 Test the EBCM ground circuits with a test lamp connected to B+.
Does the test lamp illuminate for all circuits?
Go to Step 12  Go to Step 24 
12 Test the EBCM serial data circuit for an open, high resistance, or short circuit. Refer to Circuit Testing in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 13 
13 Inspect the EBCM connectors. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 26 
14  Does the scan tool communicate with the SIR module? Go to Step 19  Go to Step 15 
15 Test the SIR module battery positive (B+) and/or ignition voltage circuits with a test lamp to ground.
Does the test lamp illuminate for all circuits?
Go to Step 19  Go to Step 24 
16 Test the SIR module ground circuits with a test lamp connected to B+.
Does the test lamp illuminate for all circuits?
Go to Step 17  Go to Step 24 
17 Test the SIR serial data circuit for an open, high resistance, or short circuit. Refer to Circuit Testing in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 18 
18 Inspect the SIR module connectors. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 27 
19  Does the scan tool communicate with the theft deterrent module? Go to Step 29  Go to Step 20 
20 Test the theft deterrent module battery positive voltage B+ and/or ignition voltage circuits with a test lamp to ground.
Does the test lamp illuminate for all circuits?
Go to Step 21  Go to Step 24 
21 Test the theft deterrent module ground circuits with a test lamp connected to B+.
Does the test lamp illuminate for all circuits?
Go to Step 22  Go to Step 24 
22 Test the theft deterrent serial data circuit for an open, high resistance, or short circuit. Refer to Circuit Testing in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 23 
23 Inspect the theft deterrent module connectors. Refer to Wiring Repairs or Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 29  Go to Step 28 
24 Repair the circuit as necessary. Refer to Wiring Repairs or Connector Repairs .
Is the action complete?
Go to Step 29  -
25 Replace the ECM.
Is the action complete?
Go to Step 29  -
26 Replace the EBCM. Refer to Brake Modulator Assembly Replacement in Antilock Brake System.
Is the action complete?
Go to Step 29  -
27 Replace the SIR module. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement in SIR.
Is the action complete?
Go to Step 29  -
28 Replace the theft deterrent module> Refer to Theft Deterrent Control Module Replacement in Theft Deterrent.
Is the action complete?
Go to Step 29  -
29 Operate the system in order to verify the repair.
Is the action complete?
System OK Go to Step 3