Cadillac Repair: ECC problem, cadillac fleetwood, mileage indicator

Question
My question concerns a 1983 Cadillac Fleetwood 4.1 engine(gasoline). The problem began a few days ago. Normally when the car is started, there is an indicator light above any given button(off,low,high,etc...) on the climate control panel. There seemed to be an intermittancy in that lately, one day it works, the next day it doesn't. Now its out and has not worked for a couple of days. Additionally, the fuel mileage indicator to the right of the ecc is out as well. Now this is the strange part; every so often, both service soon and service now indicators will light up for a second or two and then go off. I hope you able to help. Thanks in advance!
Bill  

Answer
It appears that you have more than ONE problem here.

OK, let's concentrate on diagnosing WHY both service soon and service now indicators will light up for a second or two and then go off.


Have a piece of paper and a pencil in hand.

1. turn the ignition key to the ON position. Do NOT start the engine.

2. depress and hold the OFF and WARMER buttons on the climate control panel IN at the same time until you see -1.8.8 and then RELEASE the OFF and WARMER buttons.

3. Write down the numbers that appear on the climate control panel and HOW MANY TIMES each number appears.

4. Once all the numbers display you will see .7.0

5. Turn OFF the ignition key.

6. Let me know what numbers and how many times they apperaed.



as far as the climate control lights and the fuel mileage display being inoperative this could be either a fault in the ECC PROGRAMMER and or a fault within the computer itself.

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