12 volt constant on self test
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From: St Louis
Just use your CEL light and count the flashes. There is no need to use a meter.
If the light stays off and never flashes when KOEO PCM Quick Test is initiated, then there is a problem related to the operation of the PCM.
Steve
If the light stays off and never flashes when KOEO PCM Quick Test is initiated, then there is a problem related to the operation of the PCM.
Steve
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From: Easton,Ks
Originally Posted by buckethead5k
86 f150 300 i6. when I try to do a self test using both the haynes and fordfuelinjection.com versions it doesn't flash it just shows a constant 12 volts any clue
Are you then grounding the white wire with a red stripe at the self-test connector (from EEC Module pin #48) and then turning on the key?
You can use the Black wire with a white stripe at the test connector for ground.
Last edited by subford; Nov 24, 2007 at 12:01 PM.
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From: Easton,Ks
Originally Posted by projectSHO89
Just use your CEL light and count the flashes. There is no need to use a meter.
If the light stays off and never flashes when KOEO PCM Quick Test is initiated, then there is a problem related to the operation of the PCM.
Steve
If the light stays off and never flashes when KOEO PCM Quick Test is initiated, then there is a problem related to the operation of the PCM.
Steve
He will have to use a meter (no test light) as I think a test light will blow the 2K resister that is between battery voltage and the test point.
12V is normal at the test point when the EEC Module is not running the self-test.
/
Last edited by subford; Nov 24, 2007 at 12:39 PM.
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From: Virginia
How big is the resistor? If you grounded out the tan/red wire, that would put 12 volts across the 2k resistor. 12v divided by 2000 ohms =.006amps through the resistor. 12v x .006a =.072 watts. An 1/8 watt resistor would handle it, though a 1/4 watt would be even better.
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From: Easton,Ks
Originally Posted by Franklin2
How big is the resistor? If you grounded out the tan/red wire, that would put 12 volts across the 2k resistor. 12v divided by 2000 ohms =.006amps through the resistor. 12v x .006a =.072 watts. An 1/8 watt resistor would handle it, though a 1/4 watt would be even better.
/
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sorry for the slow reply. Ok I tried the test again and still its constant 12 volts but I noticed that even with the keys in my pocket it still constant 12 volts. maybe its a bad ground?
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From: Easton,Ks
By the way the right way to hook the meter to the self-test connector is to hook the positive wire of the meter to the positive post of the battery and the negative wire to the test connector. Also the test light if used should be between the positive post of the battery and the test connector.
The above diagram was for a discussion we were having about the resister and you getting 12 volts at the test connector.
That said I would pull your EEC Power Relay and see if the 12 volts goes away. If not check to see if somebody has bypassed the relay.
Also make sure the black wire with a green stripe is well grounded at the negative post of the battery.
The above diagram was for a discussion we were having about the resister and you getting 12 volts at the test connector.
That said I would pull your EEC Power Relay and see if the 12 volts goes away. If not check to see if somebody has bypassed the relay.
Also make sure the black wire with a green stripe is well grounded at the negative post of the battery.
Last edited by subford; Nov 27, 2007 at 09:17 AM.
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From: Easton,Ks
I was just wondering why you were trying to do the self-test.
Is the engine running bad?
I take it you do not have FI.
I was thinking that you may have a bad ECU Computer but not sure what to look for on a non-FI truck with no SPOUT shorting bar and that has a TFI ignition.
Is the engine running bad?
I take it you do not have FI.
I was thinking that you may have a bad ECU Computer but not sure what to look for on a non-FI truck with no SPOUT shorting bar and that has a TFI ignition.