For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
Important: A short to ground will cause an open fuse(s). Before performing this diagnostic procedure, inspect the fuse(s) for an open.
1 | Was the Instrument Cluster Diagnostic System Check performed? | -- | Go to Step 2 | Go to Diagnostic System Check - Instrument Cluster
2 |

1. Start the engine.
2. Use the Scan Tool in order to read the BFC to cluster data.

Is the Tach Signal reading active?

--

Go to Step 5

Go to Step 3

3 |

1. Disconnect the instrument cluster.
2. Use the J 39200 DMM in order to measure the AC voltage in CKT 121 at connector terminal A7 of the instrument cluster.

Does an AC voltage exist?

--

Go to Step 4

Go to Step 5

4 | Replace the instrument cluster. Refer to Instrument Cluster Replacement . Is the repair complete? | -- | Go to Diagnostic System Check - Instrument Cluster | --
5 | Test for a short to ground in CKT 121. Was a short to ground found? | -- | Go to Step 6 | Go to Step 7
6 | Repair the short to ground in CKT 121. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - Instrument Cluster | --
7 | Use the J 39200 DMM in order to measure the resistance in CKT 121. Does the resistance measure within the specified range? | 0-2 ohms | Go to Step 9 | Go to Step 8
8 | Repair the open in CKT 121. Refer to Wiring Repairs in Wiring Systems. Is the repair complete? | -- | Go to Diagnostic System Check - Instrument Cluster | --
9 | Replace the powertrain control module (PCM). Refer to Powertrain Control Module Replacement/Programming in Engine Controls. Is the repair complete? | -- | Go to Diagnostic System Check - Instrument Cluster | --