2017 Toyota RAV 4 installation

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RFI-EMI-GUY

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I'm curious, are the problems related only to charging and power management? Also "current sensor loop" ? I assume you mean that figuratively and not through an actual CT?

The power management problem is only a new complication to using the negative battery pole from grounding radios, the others:

1) Failure of the bonding cable between battery negative terminal and the chassis will cause return current from the starter to flow through the radio negative lead and dissipate in radio antenna cable burning the headliner. In the older simpler days, a failure like this commonly burned the speedometer cable.

2) Every other load in the vehicle goes directly to the chassis. The motors like the engine fans, the HVAC fans, AC Clutch, wipers, plus alternator etc etc, .. If you connect the radio at the battery negative post there will be a small inductance/resistance that will allow those motors and alternator to introduce whine and noise into your radio. You want a common ground with all the other equipment.
 

bharvey2

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The power management problem is only a new complication to using the negative battery pole from grounding radios, the others:

1) Failure of the bonding cable between battery negative terminal and the chassis will cause return current from the starter to flow through the radio negative lead and dissipate in radio antenna cable burning the headliner. In the older simpler days, a failure like this commonly burned the speedometer cable.

2) Every other load in the vehicle goes directly to the chassis. The motors like the engine fans, the HVAC fans, AC Clutch, wipers, plus alternator etc etc, .. If you connect the radio at the battery negative post there will be a small inductance/resistance that will allow those motors and alternator to introduce whine and noise into your radio. You want a common ground with all the other equipment.


Hmm. Looks like I missed your post earlier. In any case, I do understand the problem you mentioned. Although I've never had major problems as a result of the bonding failure, I've seen deterioration of the connections both at the battery and at the chassis bonding point so I do periodic maintenance to the connections, cleaning them up and re-establishing good connections. That only reduces and doesn't eliminate a future problem as you pointed out. Although I've never encountered it, I understand the rationale behind fusing the negative lead. Thanks for the clarification RFI-EMI-GUY.
 

cmdrwill

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The radio power Negative cable needs to be 'grounded' to the vehicle body near the radio. So you will NOT "have any major problems".
 
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bharvey2

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The radio power Negative cable needs to be 'grounded' to the vehicle body near the radio. So you will NOT "have any major problems".


A fairly easy fix. A new negative Powerpole terminal with about a 16" lead. Fab'd a small lug to go under the seat bolt (shown in one of the photos) The new lug has a 1/4" hole for a terminal screw/bolt. 16" lead bolts to new lug. Sorry no picture of that.
 

mrweather

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The radio power Negative cable needs to be 'grounded' to the vehicle body near the radio. So you will NOT "have any major problems".
My Dodge Charger has a specific stud near the battery that the owner's manual prescribes is to be used as the grounding point for two-way radios installations.
 
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