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1984 Daytona won't start

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I have an '84 Daytona with turbo that has been garaged and not started in over 6 years. Ran fine before that. I have the Chrysler service manual for the car purchased when I bought the car new. I'm the original owner.

I get two fault codes: 12 and 42. I understand 42 but not 12. The shop manual states the following: "CODE 12 indicates a problem in the stand-by memory circuit. This code appears if direct memory feed to the Logic Module is interupted." I would have thought the "stand-by memory circuit" was in the Logic Module, but I do not get Code 44 which indicates a problem in the Logic Module.

I've made quite a few tests. The ASD relay (or fuel pump relay) is shutting down in about a second. However, I get a spark before shut down. Pulled all 4 plugs and tried starting numerous times to see that a plug fires once each attempted start. All 4 have fired at different times. I have pressure on the rail and appears the injectors are not plugged as I get a mist in the cylinders when I apply current to the injectors. I did a successful continuity test on all the lines from Power Module and Logic Module connectors (disconnected from the moduels) to the source input/interface connector (also disconnectred). The Power Module puts out 12v, 7.5v and 5v to the proper circuits. The grounds are all OK.

I presume that Code 42 is triggered because of the Code 12 problem is causing the Logic Module to interupt the starting sequence. What is the "stand-by memory circuit", and what "direct memory feed to the Logic Module" could cause the problem in the "stand-by circuit"?

Thanks to anyone who can give me a lead on this.

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· Super Moderator
1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
17,028 Posts
I think that you can ignore code 12 as the car has presumably just had the 12 volts re-applied after storage. That would be a normal code for a battery reconnect. It is just saying that the battery keep-alive memory for the logic adaptives and fault code memory was lost.
The start/stall may be from the logic module not seeing engine rotation and shutting off the ASD/fuel pump relay. Does it continue running if you spray a carb/throttle body solvent into the air intake or jump the ASD relay contacts? The pressurized fuel rail shows the fuel pump is working, but the injectors may be kept turned-off and not be spritzing their fuel. If the distributor pick up stops sending the ignition/sync signal pulses, the logic module will shut down the engine.

· Registered
5,968 Posts
With it sitting for so long and not being driven, I think I'd start by looking at every electrical connector under the hood, for corrosion. The first place I'd look would be at the battery for corrosion under the cables. Next would be the actual connectors to the power module and logic module. Keep in mind, that I am not a mechanic, so am sure you'll get better advice from some other members that really know these cars. For example, Bob O'Neil and Bob Lincoln.
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