Headlights on when battery charger is hooked up. Why?

[Wmoater]

Strange thing going on. I have my spyder up on lift. It was working and started just fine 2 days ago. Installed new airbag. Wanted to test everything before I reinstall shock. Turned spyder on to start and it’s dead. Checked connection real quick all good. Checked volts and it’s dead. Must have left something on to kill it. So hooked up jump start and spyder starts immediately without hesitation. Checked volts yep pulling 14.4 so it’s charging too. Turned machine off and hooked up a charger to charge battery. Headlights turn on, with key out and they won’t go off? Is that normal or do I need to totally disconnect everything to charge? Why would headlights be on while charging? I disconnected and for giggles connected in my tenderizer that I use over winter. Headlights not on but bikes taking a charge. Why are headlights on when charging dead battery? Sort of defeats the purpose.

 

[Wmoater]

Now that’s really strange. No tail or running lights are on when charging. I just jump started again and they all come on as normal. Turned off machine. Sits for 30 seconds everything clicks off (dash, headlights, taillights) connect charger and headlights come on again but nothing else. I just disconnected everything and removed battery and starting to charge. Any ideas why headlight come on while charging?

 

[DGoebel]

opcorn: Any add-on lights or electric farkles? are you connecting the charger direct to the battery terminals or have a remote connection point?

 

[CloverHillCrawler]

Sounds like you have a backfeed you need to find, if everything was ok before the airbag install start there to make sure no connections are crossed or polarity reversed .

If there are any accessories directly connected to the battery I would disconnect those as well as a starting point to start troubleshooting.

Check for any nicks or exposed conductors around the area you were working in.

 

[BajaRon]

opcorn: Any add-on lights or electric farkles? are you connecting the charger direct to the battery terminals or have a remote connection point?

My first thought.

Sounds like you have a backfeed you need to find, if everything was ok before the airbag install start there to make sure no connections are crossed or polarity reversed .

If there are any accessories directly connected to the battery I would disconnect those as well as a starting point to start troubleshooting.

Check for any nicks or exposed conductors around the area you were working in.

My 2nd thought. Seems like it would have to be one of these 2. Or possibly a bad ground somewhere. Wiring issues can be a bear to troubleshoot.

Disconnect one wire at a time so that if you cure the issue. You know what cured it.

 

[BertRemington]

I walked through the circuit flow again and backfeed would be exceptionally difficult to achieve. Essentially the Lo Beam circuit is Always-On with RFB R2 N-O terminals closing only when commanded by the ECM. So to achieve a backfeed you would have to carefully search out, isolate and connect to the Lo Beam side of RFB R2. Unlikely is applicable here.

WRT ground, Yes if the RFB R2 - Coil connection (nominal Pin 85 in ISO terms) was grounded but then the Lo Beam would be illuminated all the time not just when charging.

I keep returning to something is telling the ECM the engine is running and therefore it commands RFB R2 to close.

I looked at the TAS (two Hall Effect sensors) wiring and the PedalBox installation video. Maybe the service manual explains but I'm thinking the TAS is like the ABS with an encoded tone wheel which has a No-Throttle and a Full-Throttle code. The PB sits between the TAS and ECM and must be trained with No and Full throttle positions while the ignition is On (engine NOT running) which means the PB (1) gets its power soley from the ECM and (2) emulates the Hall Effect sensors. My conclusion is even an improperly installed PB will not cause the ECM to determine the engine is running and therefore command RFB R2 to close.

Which brings us back to ... wiring damage when the Spyder was on the lift.

 

[BajaRon]

I walked through the circuit flow again and backfeed would be exceptionally difficult to achieve. Essentially the Lo Beam circuit is Always-On with RFB R2 N-O terminals closing only when commanded by the ECM. So to achieve a backfeed you would have to carefully search out, isolate and connect to the Lo Beam side of RFB R2. Unlikely is applicable here.

WRT ground, Yes if the RFB R2 - Coil connection (nominal Pin 85 in ISO terms) was grounded but then the Lo Beam would be illuminated all the time not just when charging.

I keep returning to something is telling the ECM the engine is running and therefore it commands RFB R2 to close.

I looked at the TAS (two Hall Effect sensors) wiring and the PedalBox installation video. Maybe the service manual explains but I'm thinking the TAS is like the ABS with an encoded tone wheel which has a No-Throttle and a Full-Throttle code. The PB sits between the TAS and ECM and must be trained with No and Full throttle positions while the ignition is On (engine NOT running) which means the PB (1) gets its power soley from the ECM and (2) emulates the Hall Effect sensors. My conclusion is even an improperly installed PB will not cause the ECM to determine the engine is running and therefore command RFB R2 to close.

Which brings us back to ... wiring damage when the Spyder was on the lift.

I am assuming no codes. Usually, if there is damage to a sensor or wiring harness, that will throw codes. But you can't always trust those as low battery voltage will also cause the ECM to throw random, unrelated codes.

 

[IdahoMtnSpyder]

I am assuming no codes. Usually, if there is damage to a sensor or wiring harness, that will throw codes. But you can't always trust those as low battery voltage will also cause the ECM to throw random, unrelated codes.

There were. Check this thread for the full story. https://www.spyderlovers.com/forums...ors-P0123-P2135-P284E-P2806-Please-help/page2

 

[2dogs]

My first thought.



My 2nd thought. Seems like it would have to be one of these 2. Or possibly a bad ground somewhere. Wiring issues can be a bear to troubleshoot.

Disconnect one wire at a time so that if you cure the issue. You know what cured it.

Right on Ron! I just finished a two day battle with an electrical issue on a different machine. It was a loose ground attached with a squeeze connector located in an unseeable location. I finally fingered everything rather than just looking and it fell loose without any pressure applied at all. So you never know. It came from the factory that way.

 

[Bensonoid]

Wmoater, what did you remove to get at your airbag to replace it?

 

[happyspyder2039]

Because they are afraid they will be tenderized!!!