I have a dodge grand caravan 2006 with trouble

Hi, sorry I don't have a manual for your van but here is some general information for these codes.

P0126 Insufficient Coolant Temperature for Stable Operation:

basically, the engine is running cool. Check your thermostat to see if it's closing properly. If it is closed when removed, you may want to get a higher temp thermostat. The thermostat is usually in a housing bolted to the engine at the end of the upper radiator hose.


P0406 Exhaust Gas Recirculation Sensor A Circuit High:

This indicates the EGR position sensor signal is out of range. The problem could be the wiring or the sensor itself. Check the wiring first. If it looks good, consider replacing the sensor. I think in your van the sensor may be integrated into the EGR valve itself.

EGR valve:

1. Drain the cooling system.
2. Remove the engine cover.
3. Disconnect the Inlet hose from the housing.
4. Remove the thermostat housing bolts (A), thermostat housing (B), and the Thermostat (D).
5. Clean the gasket mating surfaces and the housing and intake port.

To Install:

1. Install the Thermostat (D).
2. Install the thermostat housing (B) with a new gasket (C) and torque the bolts (A) to 15 ft-lb (20 Nm).
3. Connect the inlet hose.
4. Install the engine cover.
5. Refill the cooling system.

To Drain:
NOTE: Draining the cooling system with the pressure cap installed will siphon the coolant from the overflow tank.

1. Raise and support the vehicle.
2. Open the radiator drain **** and drain the coolant into a drain pan.
3. Empty and wash out the coolant reservoir with soap and water.
4. Inspect the coolant if discolored flush the system before refilling.

To Fill:
CAUTION
Follow the procedure below to insure the coolant is at the proper level. A coolant level that is too high or too low could cause engine damage.

1. Close the radiator drain **** and lower the vehicle.
2. Slowly fill the cooling system with a 50/50 mixture of DEX-COOL antifreeze and clean drinkable water.
3. Install the coolant pressure cap and start the engine.
4. Run the engine at 2,000-2,500 RPM until the engine reaches normal operating temperature than let the engine idle for 3 minutes.
5. Turn the engine off and let the engine cool off.
6. Top off the coolant and check the concentration of the coolant using the (J 26568) coolant and battery tester.

CODE PO126 - INSUFFICIENT COOLANT TEMPERATURE FOR STABLE OPERATION. CHECK FOR LOW COOLANT LEVEL.FAULTY THERMOSTAT STUCK OPEN.OR MISSING THERMOSTAT.FAUTY COOLANT TEMPERATURE SENSOR. CODE PO230 - FUEL PUMP PRIMARY CIRCUIT MALFUNCTION.POSSIBLE CAUSE FAULTY FUEL PUMP RELAY.OR PCM CIRCUIT FAILURE TO FUEL PUMP RELAY. DID NOT SEE CODES P1693 AND P1689.

This code is for your Coolant Thermostat - It's detected that the Coolant Temperature is below the Thermostat Regulating Temperature

This code may mean one or more of the following has occurred:

• Low engine coolant level
• Leaking or stuck open thermostat
• Cooling fan running too much
• Faulty coolant temperature sensor (ECT)
• Faulty intake air temperature sensor (IAT)

Check the following to see if it resolves your problem:

• verify coolant strength and level
• verify cooling fan operation and replace if necessary
  
• verify ECT sensor operation and replace if necessary
• verify IAT sensor operation and replace if necessary
• if all above checks out, replace the thermostat