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Discussion Starter #22
Here are some test I have done so far. Each time I monitored test probe while turning key on.

1-12 ignition input at ASD to positive = 12.6v

1-58 ASD signal at ASD to negative = 0

2-3 ignition input at dia. conn to positive = 12.6 v
 

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Your ASD power feeds have to be present or the ASD would not have actuated when you manually actuated the ASD Relay.

Your issue due to the fact that the ASD will not actuate for 1 second with initial key on seems to be that either the controller does not know you turned the key on which would be related to the power feeds at the controller which I posted earlier or the DB/YL ground side control wire is open between the diagnostic connector and the SMEC.

We already know the circuit is complete from the diagnostic connector to the ASD relay since it actuated when you grounded it.
 

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Discussion Starter #25
Tomorrow I will back probe 1-12 , 2-3 and 2-4 at 60 pin and 14 pin connectors respectively. Which wire to the smec lets it know to actuate (send ground) the ASD? Is it 1-12. Which happens to also feed the positive side of the ASDs coil?
 

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I honestly do not which power feed the controller has to see to know the key has been turned on and it should actuate the ASD.

All I do know about the circuit is that with initial key on the ASD is actuated.
If the controller does not see a crank signal within one second of the time the ASD is actuated it turns off the ASD until a crank signal is seen.
 

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Discussion Starter #27
Hey Naj. would the distributor sync signal be present at key on? From what I have read so for thats what keeps the ASD on during" run ". And is this something that can be checked with a meter?
 

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No, the crank signal is only present during cranking and running.
It is not needed for the initial one second actuation.

That is why the question is asked...
"Does the fuel pump cycle for one second with initial key on".

If the answer is YES then the ASD circuit is fine, the controller saw "key on" and actuated the ASD relay to pressurize the fuel rail.
The assumption then if this is a no start condition is that the crank or fuel sync signal is missing during cranking so the controller will not actuate the ASD relay again because it does not see the signal.

If the answer is NO which is what you stated then there is an issue in the ASD relay circuit since you turned the key to the "on" position and the fuel pump did not cycle for one second which means the controller does not know you turned the key on or it did see the key turned on and is not able to actuate the ASD relay.
I would think that the latter would set a Code 42 since the controller attempted to actuate and did not see the ASD voltage sense.
Do not confuse this with the Code 42 that you set in memory by manually actuating the ASD relay.

Again, your issue is one of three things since you were able to manually actuate the ASD relay.
1)Loss of switched ignition voltage to controller
2)Open DB/YL wire between diagnostic connector and controller
3)Faulty SMEC.
 

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Discussion Starter #29
Cool. I was in process of checking DB/Y wire when I got rained upon. But all clear no. heading back out to check.
Wire from diagnostic connector to smec is good. The only wire I could find that comes from the ignition switch goes to cavity 1-10 Z1 voltage sense on the 60 pin connector. Key On it had no voltage.
 

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SBEC 14 Pin Cavity 4 from Ignition Switch
(this also runs to the Alternator, Rad Fan Relay and Diagnostic Connector from the Ignition Switch)

SBEC 60 Pin Cavity 12 from SBEC 14 Pin Cavity 3
(this also runs from the SBEC 14 Pin Cavity 3 to the ASD Relay
Cavity 1-10 is he ASD Relay voltage sense, that is how the controller knows if the ASD is actuated or not.

The DB wire comes from the ignition switch.
 

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Discussion Starter #31
Ok. So I have tested these points and found voltage at all of them and found continuity from 60 pin cavity 56 to diagnostic connector. I am assuming that cavity 56 is a ground to the ASD. And if so could it be a grounding issue?
 

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All diagnostic flow charts have you check voltage, grounds and wiring and the component.
If all check OK it is then assumed the controller is at fault.
The only way you can verify that is a scanner to actuate the ASD relay or a known good SMEC.

Are you 100% sure there is no voltage present for 1 second on the DG/BK ASD relay output wire when you cycle the key to the on position?

 

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Discussion Starter #34
ok hooked up Matco 4000E and actuated ASD with scanner.ASD Functioned as did pump Checked for codes and had none. Letting battery charge and will check again after turning over engine for 10 sec.
 

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If it actuated with the scanner then all of the wiring and the controller are good.

After your battery charges Please verify that there is or is not power present at the ASD Relay output wire for 1 second when you turn the key to the on position.
 

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Discussion Starter #36
Well its time for me to close up shop for the night. Thanks for all the help so far Naj. Its looking like my smec my have taken a crap.
 

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As far as I remember(been 28 years since I was in the classroom for these systems) when you use a scanner to run actuator tests it commands the controller to actuate the component so that would mean the SMEC is good, so...
Just for giggles check what I posted above.

Just an FYI, I will be out tomorrow by 8:30 AM and will not be back online again until Monday evening.
 

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Last words of wisdom for the weekend...
Started looking through the 90 2.2L/2.5L Turbo Powertrain Diagnostic Manual(Same as 89 only SMEC vs. SBEC) and three things were brought to my attention.

1)Does this vehicle have any type of theft alarm system installed that will prevent the engine from starting when activated?

2)You have another power feed that I missed looking at the wiring, constant battery feed from battery through a fusible link to the SMEC Cavity 1-41 and ASD relay on the RD wire.
Be sure voltage(12 volts) is present at both loctions.

3)If the vehicle does not have a theft alarm and voltage is present the RD battery feed at the controller and ASD relay...
The diagnostics manual has you checking voltage on the DB/YL ground wire while cranking so here is the 90 Code 42 ASD Circuit Diagnostics.
(DB/YL is cavity 58 of the SMEC)

If it leads to replace SMEC I would still like you verify if voltage is present on the DG/BK and apparently the DB/YL wire also with initial key on.
Use a test lamp and see if it illuminates for 1 second with initial key on.
a)If the test lamp does not illuminate for one second with initial key on then I would say Yes, the SMEC is faulty.
(Always remember to check connector terminal integrity before condemning the SMEC)
b)If the test lamp does illuminate for one second with initial key on I would say the ASD circuit is functioning properly and would move on to checking the HEP circuit for a loss of crank signal.

Good Luck
Hoping to see + results when I come back on Monday.



 

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Discussion Starter #40
Hey Naj funny thing happened while using my new fangled test prob on GN/BK wire at ASD. I turned the key and I hear this chirping noise. I did it two more times and the same result.:surprise: I forgot that my test prob has an audible signal.:surprise: So ASD worked those thee times them wouldnt work again. I fiddle with the ASD relay and the tester and it chirped again. I am going to ppick up a relay from local store and try it out. Wish me luck !!
 
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