Goal:
1. Power the Audio system when the key is not in the ignition
2. Keep the Pioneer AVIC from Rebooting when on short stops by flipping switch to constant power.
[EDIT: This works when shutting down the truck but it still reboots on restart...but only sometimes. I think I need to move the constant hot off of the main battery over to the aux batt.]
3. Add another switch to dash of my Cruiser
I've been meaning to do this for some weeks and had a few minutes this afternoon to do it... I wanted to be able to run my audio system with the key out of the ignition. Most German cars do this already but the ole 100 needed some help.
In the case of our Bavarian friends the radio has a retained power for about an hour then shuts off to conserve battery. Of course you can turn it right back on for another hour. Since my LC has a second battery installed I'm not too concerned about a one hour cut off time so a simple relay is all thats needed.
In my Aux battery install I have a Safety Hub 100 Fuse box in the cabin and one of my 7 circuits is being used for this project as the constant hot.
Parts:
Hella Illuminated Rocker Switch
Bosch Relay
Some 16ga Wire and Terminals
I ran the switched Power from the dash to 87a in the relay. I ran Constant from the Aux Battery to 87. I also ran constant from the Aux Battery to the hot side of the Hella Switch so it's powered at all times. Connected terminal 30 back to the head unit main power input (10 amp fused not shown). Grounded relay (86) and switch. Ran output of switch to 85. In this Bosch relay, 87a is linked to 30 until power is applied to 85 via the rocker switch. Note: The Power Antenna relay is powered only when ACC is active. That doesn't bother me since I very rarely use the AM or FM in my radio.
Results as stated in goals. That's the Hella switch above my scan gauge in the lower right.
1. Power the Audio system when the key is not in the ignition
2. Keep the Pioneer AVIC from Rebooting when on short stops by flipping switch to constant power.
[EDIT: This works when shutting down the truck but it still reboots on restart...but only sometimes. I think I need to move the constant hot off of the main battery over to the aux batt.]
3. Add another switch to dash of my Cruiser
I've been meaning to do this for some weeks and had a few minutes this afternoon to do it... I wanted to be able to run my audio system with the key out of the ignition. Most German cars do this already but the ole 100 needed some help.
In the case of our Bavarian friends the radio has a retained power for about an hour then shuts off to conserve battery. Of course you can turn it right back on for another hour. Since my LC has a second battery installed I'm not too concerned about a one hour cut off time so a simple relay is all thats needed.
In my Aux battery install I have a Safety Hub 100 Fuse box in the cabin and one of my 7 circuits is being used for this project as the constant hot.
Parts:
Hella Illuminated Rocker Switch
Bosch Relay
Some 16ga Wire and Terminals
I ran the switched Power from the dash to 87a in the relay. I ran Constant from the Aux Battery to 87. I also ran constant from the Aux Battery to the hot side of the Hella Switch so it's powered at all times. Connected terminal 30 back to the head unit main power input (10 amp fused not shown). Grounded relay (86) and switch. Ran output of switch to 85. In this Bosch relay, 87a is linked to 30 until power is applied to 85 via the rocker switch. Note: The Power Antenna relay is powered only when ACC is active. That doesn't bother me since I very rarely use the AM or FM in my radio.
Results as stated in goals. That's the Hella switch above my scan gauge in the lower right.
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