Checking the ECU for codes.

1. Pull ECU out so that you can access this slot circled in Fig. 1 , while leaving harness connected.
Enthalpy ECU FAQ 1

2. Turn key to the ignition position, but do not start car.

3. With a small Phillips screwdriver, turn the plastic screw inside the slot fully clockwise, wait 2 seconds, turn back fully counterclockwise.

4. You should receive 5 long and 5 short flashes which translates to 55 or no codes.

Retune Install

1. Remove ECU from car.

2. Remove the 4 case screws circled in Fig. 2Enthalpy ECU FAQ 2

3. Remove 4 R.S. Enthalpy board screws circled in Fig. 3 and flip board back.Enthalpy ECU FAQ 3

4. With a small flathead screwdriver slowly pry up one side of each chip (Fig.4 ).Enthalpy ECU FAQ 4

Move to opposite side once chip begins to loosen. Be delicate, as it is easy to damage existing chips / sockets. Work each chip back and forth several times so that it removes straight up rather than at an angle like in Fig 5.
Enthalpy ECU FAQ 5

5. Reinstall new chip into socket carefully. Make sure the half moon alignment marker on the chip is aligned with the white diagram below the chip socket. Fig. 6
Enthalpy ECU FAQ 6

6. If using old style R.S. Enthalpy board (Fig.7), remove board from socket on ECU and follow step 4. 
Enthalpy ECU FAQ 7

When reinstalling board make special note of the alignment between socket and ECU header. It is easy to misalign. Fig. 8 demonstrates this out of the ECU
Enthalpy ECU FAQ 8

All 62 and 63 ECUs have a red diode in slot pictured in Fig. 1 This light will illuminate red one you turn your key to the ignition position. Once you start cranking the motor, this light will go out and stay out, while the cam angle sensor detects movement; motor running. If the light stays on during cranking, there is a problem with the rom board or installation of chips. E5 and E6 ECUs use the check engine light to perform this function.