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JAG1

Questions For Electronics Experts?

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Would there be any advantage to running a separate heavy ground cable from the PCM to the negative battery post? Would it help/ possibly save the PCM in the event of any future electronic abnormalities?Second; How about an external voltage regulator using a mechanical type regulator. I say mechanical type because if it starts acting up all you need do usually, is emery cloth the contact points. It is also has a feature of being able to adjust the voltage simply by adjusting the spring screw.Third, is it possible that the ECM Could avoid future damage if it did not have to run the lift pump and/or the AD Raptor relay? Asking because I would use an oil pressure switch that would kick in the AD Raptor pump without the relay.I thank everyone for any thoughts. Maybe going the wrong path, who knows?...... just need input from the experts.

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Would there be any advantage to running a separate heavy ground cable from the PCM to the negative battery post?

Already done. :thumbup2: The PCM is direct connected to the passenger side battery terminal and has no tie to the body.

Would it help/ possibly save the PCM in the event of any future electronic abnormalities?

No. Because most are either weak ground connections (corroded terimnals) or bad alternator diodes.

Second; How about an external voltage regulator using a mechanical type regulator. I say mechanical type because if it starts acting up all you need do usually, is emery cloth the contact points. It is also has a feature of being able to adjust the voltage simply by adjusting the spring screw.

I think the mechanical regulator would be way too harsh on the electronics with the pulse hi and pulse lo type charging like back in the old days there wasn't any electronics really just lights and switches.

Third, is it possible that the ECM Could avoid future damage if it did not have to run the lift pump and/or the AD Raptor relay? Asking because I would use an oil pressure switch that would kick in the AD Raptor pump without the relay. I thank everyone for any thoughts. Maybe going the wrong path, who knows?...... just need input from the experts.

As for the relay style hook like AirDog and FASS is the best way to hook up the lift pump and keep the heavy current draw off the ECM and prevents damage. But the biggest cause of damage is AC noise that is either cause from loose alternator connection, bad alternator diodes, or bad alternator field brushes... Because technically if the batteries would hold up for ever and never need external charging the ECM and PCM would never take on damage.

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Has prepper written all over it ;)Mechanical VRs work well, but they're just not as precise as their electronic counterparts.As for grounding, all I can go on is my past mobile audio/video experience as a Master Installer (MECP-certified) and tell you:In order to ensure the least chance for noise introduction is to keep the ground wire as short and tight as possible, no longer than 18 inches, and clean the ground-points regularly.The Oil Pressure switch is not designed to carry the amperage that a Raptor would draw, thus requiring a relay, anyway.

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Okay, so my only concern left is the lift pump activation relay..... Is there any benefit to getting activation from another source other than the ecm even though it is just activating a power relay? On a side note, I looked for the pcm grounding to the passenger battery. I have 3 cold air intake hoses and the stock air box in the way. I need the BHAF to eliminate that and be able to see in there anytime.

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Realy for the lift pump is safe the current draw is small. I bet Rogan can tell you how much current in mA it takes to trigger a relay. :whistle:

Huh.... interesting. Thank you Mike and appreciate all the answers. So just watch the pcm and ecm grounds real well. Clean emery cloth them each year right? :thumbup2: Oh Mike, there is another ground from the PCM to the firewall. Its on the engine side of PCM.

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Huh.... interesting. Thank you Mike and appreciate all the answers.

So just watch the pcm and ecm grounds real well. Clean emery cloth them each year right? :thumbup2:

Oh Mike, there is another ground from the PCM to the firewall. Its on the engine side of PCM.

No. There is no other ground. The PCM is on the passenger side firewall and the ECM is on the driver side of the engine block. The PCM gets it ground direct from the passenger side ground cable. Then the ECM and VP44 get there ground from the driver side battery cable.

As for maintaining my battery cables I never even mess with them, I never bother to clean them, I never have to put sandpaper or wire brush to them. How you might ask? I keep them coated with engine oil that's all.

Posted Image

Remember I'm the battery king... :lol: My whole house is ran off of 24V battery system.

post-2-138698191961_thumb.jpg

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Interesting...... my truck is from the last of the second gens. Built in October 2002 it has a second ground going to the firewall:wow:. Want pics??

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200mA, or .2A is all it takes to trigger a standard (i.e. Bosch) relay. ;)

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