Scan Tool Does Not Communicate with Memory Seat Module
WARNING: This page is about a different car, the 2000 Cadillac Catera. However, it is still accessible from the selected car via links, so may be relevant.
SCAN TOOL DOES NOT COMMUNICATE WITH MEMORY SEAT 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) * Memory Seat Module (MSM) * Transmission Control Module (TCM) Does the scan tool communicate with the other modules? |
-- | Go to Step 3 | Go to Step 20 |
| 3 | 1. Disconnect the memory seat module (MSM) connector C1. 2. Measure the resistance between the MSM connector C1 terminal 6 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 the ECM connector. 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 connector C1 terminal 6. 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 the MSM serial data circuit. Is the repair complete? |
-- | Go to Step 9 | -- |
| 7 | Replace the ECM. Is the replacement complete? |
-- | Go to Step 9 | -- |
| 8 | 1. Reconnect the ECM. 2. Disconnect connector C1 from the MSM. 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 MSM. Does the scan tool communicate with the MSM? |
-- | System OK | -- |
| 10 | 1. Inspect the PWR SEAT fuse for an open. 2. Inspect and test the MSM battery feed circuit at terminals 1 and 3 for proper voltage (11-13 V). 3. Inspect and test the MSM ground circuits at terminals 2 and 5. 4. Make necessary repairs. Did you find and correct any conditions? |
-- | Go to Step 9 | Go to Step 12 |
| 11 | Replace the TCM. Is the replacement complete? |
-- | Go to Step 9 | -- |
| 12 | Replace the MSM. Is the replacement complete? |
-- | Go to Step 9 | -- |
| 13 | 1. Reconnect the MSM. 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. 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 terminal 88 * Instrument Cluster connector terminal 24 * Memory Seat Module connector C1 terminal 6 * TCM connector terminal 13 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 | -- |