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Scan Tool Does Not Communicate with Transmission Control Module

SCAN TOOL DOES NOT COMMUNICATE WITH TRANSMISSION CONTROL MODULE

Step Action Value(s) Yes No
1 Was the Data Link Communications Diagnostic System Check performed? -- Go to Step 2 Diagnostic System Check - Data Link Communications 
2 Attempt to establish communication with the other modules connected to the circuit.
* Engine Control Module (ECM)
* Instrument Cluster
* Memory Seat Module
Does the scan tool communicate with the other modules?
-- Go to Step 3 Go to Step 20
3 1. Disconnect the transmission control module (TCM) connector.
2. Measure the resistance between the TCM connector terminal 51 and the data link connector (DLC) terminal 7.
Does the resistance measure less than the specified value?
.5 ohms Go to Step 5 Go to Step 6
4 1. Disconnect ECM connector C2.
2. Attempt to communicate with the other modules.
Does the scan tool communicate with the other modules?
-- Go to Step 7 Go to Step 8
5 Inspect for poor connections at TCM connector terminal 51. Refer to TESTING FOR INTERMITTENTS & POOR CONNECTIONS
Did you find and correct the poor connection condition?
-- Go to Step 9 Go to Step 10
6 Locate and repair an open in CKT XM12 (BRN/WHT).
Is the repair complete?
-- Go to Step 9 --
7 Replace the ECM.
Is the replacement complete?
-- Go to Step 9 --
8 1. Reconnect ECM connector C2.
2. Disconnect connector C1 from the memory seat module.
3. Attempt to communicate with the other modules.
Does the scan tool communicate with the other modules?
-- Go to Step 12 Go to Step 13
9 Attempt to establish communications with the TCM.
Does the scan tool communicate with the TCM?
-- System OK --
10 1. Inspect the FLASHER fuse for an open.
2. Inspect and test the TCM ignition feed circuit (CKT X837) at terminal 54 for proper voltage (11-13 V), with the key ON.
3. Inspect and test the TCM ground circuits (CKTs F819 and F836) at terminals 6 and 28.
4. Make necessary repairs.
Did you find and correct any conditions?
-- Go to Step 9 Go to Step 11
11 Replace the TCM.
Is the replacement complete?
-- Go to Step 9 --
12 Replace the memory seat module.
Is the replacement complete?
-- Go to Step 9 --
13 1. Reconnect the memory seat module.
2. Disconnect the TCM connector.
3. Attempt to communicate with the other modules.
Does the scan tool communicate with the other modules?
-- Go to Step 11 Go to Step 14
14 1. Reconnect the TCM connector.
2. Disconnect the instrument cluster connector.
3. Attempt to communicate with the other modules.
Does the scan tool communicate with the other modules?
-- Go to Step 15 Go to Step 16
15 Replace the instrument cluster.
Is the replacement complete?
-- Go to Step 9 --
16 1. Disconnect each module on the serial data circuit (DLC terminal 7).
2. Test the serial data circuit, of the DLC, for a short to ground.
3. Test between terminal 7 and the following terminals at each module:
* ECM connector C2 terminal 53
*
Instrument Cluster connector terminal 24
* Memory Seat Module connector C1 terminal 6
* TCM connector terminal 51
Did you find a short to ground in the serial data circuit?
-- Go to Step 17 Go to Step 18
17 Locate and repair the short to ground in the serial data circuit.
Is the repair complete?
-- Go to Step 9 --
18 Test the serial data circuit, of the DLC, for a short to voltage between terminal 7 and each module. (Turn ON the ignition, leaving the engine OFF, when testing for a short to voltage.)
* ECM connector C2 terminal 53
* Instrument Cluster connector terminal 24
* Memory Seat Module connector C1 terminal 6
* TCM connector terminal 51
Did you find a short to voltage in the serial data circuit?
-- Go to Step 19 Go to Step 21
19 Locate and repair the short to voltage in the serial data circuit.
Is the repair complete?
-- Go to Step 9 --
20 1. Turn OFF the ignition.
2. Disconnect the scan tool from the data link connector (DLC).
3. Inspect for poor connections/terminal tension at the DLC terminal 7. Refer to TESTING FOR INTERMITTENTS & POOR CONNECTIONS
Did you find and correct a poor connection condition?
-- Go to Step 2 Go to Step 4
21 Test the serial data circuit, of the DLC, for an open between terminal 7 and each module.
* ECM connector C2 terminal 53
* Instrument Cluster connector terminal 24
* Memory Seat Module connector C1 terminal 6
* TCM connector terminal 51
Did you find an open in the serial data circuit?
-- Go to Step 9 --