* 12: This is a system voltage code. It usually means the system check has completed successfully. It's not a fault code in itself, but it's important to see as it shows the system is at least somewhat functional.
* 43: This indicates a problem with the Crankshaft Position Sensor (CKP) circuit. The CKP sensor is crucial for the engine's timing. A faulty CKP sensor can prevent the engine from starting, cause rough running, misfires, or stalling.
* 55: This code signifies the end of the diagnostic trouble code sequence. Similar to code 12, it's not an error itself, just an indicator that the system has finished reporting codes.
Therefore, the primary problem indicated is code 43 (Crankshaft Position Sensor Circuit).
What to do:
1. Check the CKP Sensor: Locate the crankshaft position sensor (it's usually near the crankshaft pulley). Inspect it for physical damage (broken wires, corrosion). A visual inspection might not always find the problem, though.
2. Check the CKP Sensor Wiring: Carefully examine the wiring harness connected to the CKP sensor for broken wires, loose connections, or chafing against other parts. Repair or replace damaged wiring as needed.
3. Check the Connector: Make sure the connector is securely plugged into the sensor and that the pins aren't bent or corroded. Clean the connector with electrical contact cleaner if necessary.
4. Test the CKP Sensor: This requires a multimeter and some technical knowledge. You'll need to check the sensor's resistance and potentially its signal output while cranking the engine. A Haynes or Chilton repair manual for your specific year and engine will give you the correct testing procedures.
5. Replace the CKP Sensor: If the wiring and connector are fine, the sensor itself is likely faulty and needs to be replaced. This is often the most effective solution.
Important Considerations:
* OBDI Limitations: OBDI systems are less sophisticated than later OBDII systems. The codes are less specific, so further testing might be necessary.
* Year and Engine: The exact location of the CKP sensor and testing procedures may vary slightly depending on the specific year and engine size of your 1996 Dodge Dakota. Consult a repair manual specific to your vehicle.
* Professional Help: If you're not comfortable working on your vehicle's electrical system, it's best to take it to a qualified mechanic.
Replacing the CKP sensor is relatively straightforward, but improper diagnosis can lead to unnecessary part replacement. A repair manual will be your best friend in troubleshooting this issue.
