Dual transistor issue with ESP32

Thread Starter

Freddp

Joined Jan 13, 2020
2
Somewhat new to all this DC electronics, but I try to research alot and learn. But I have one issue with a module for my motorcykle i can't figure out.

I'm trying to start the bike trough my ESP32/Arduino board. two connections and relays, one is power to the bike and fulepump etc that needs power all the time, the other is the ignition that just needs power at the start, so I have to split it up.
Both have 150mA at start and then down to around 40mA, with 12v.
If i connect one circit to ether the power circuit/relay or to the ignition circuit/relay it works fine.
But as soon as I connect both of them (as the diagram) at the same time all hell breaks loose. Ether nothing works, or the bike starts right away or only the ignition works etc etc. Everything but correct. It feels like the ground to the Arduino/ESP32 is the issue, but I dont know how to solve it any other way.

I start to get crazy with this now and have searched for days, but I cant find a simular problem. Please have understanding with my bad diagram but I try as good as I can.
 

Attachments

dl324

Joined Mar 30, 2015
10,002
Welcome to AAC!

How are you powering the Arduino? Do you have snubber diodes on the relay coils?

The way you have the LEDs connected, they'll never turn on. If they turned on, they might burn out without current limiting resistors.
 

ci139

Joined Jul 11, 2016
1,179
your schematic has a bug -- the LED-s can't be shorted to ground unless the patch of (the GND) wire has signifficant length and amperage in between the anodes and cathodes (don't react to this post it's just FYI)
 

Thread Starter

Freddp

Joined Jan 13, 2020
2
Welcome to AAC!

How are you powering the Arduino? Do you have snubber diodes on the relay coils?

The way you have the LEDs connected, they'll never turn on. If they turned on, they might burn out without current limiting resistors.
Thanks!

Sorry, the leds are missleading maybe, there is no led. The cable goes to a ECM to maybe indicate some other things, I have no clue what it does in there. But the transistors are after the relays atleast.

The Arduino is just powerd through computer USB.
 

dl324

Joined Mar 30, 2015
10,002
Do you have snubber diodes on the relay coils?

If one of the circuits needs power all of the time, why do you need a relay to do that? If you eliminate one relay, it sounds like your circuit works?

Aren't you concerned that unreliable circuit operation could cause problems even if you only used one relay?
 

MisterBill2

Joined Jan 23, 2018
5,188
Somewhat new to all this DC electronics, but I try to research alot and learn. But I have one issue with a module for my motorcykle i can't figure out.

I'm trying to start the bike trough my ESP32/Arduino board. two connections and relays, one is power to the bike and fulepump etc that needs power all the time, the other is the ignition that just needs power at the start, so I have to split it up.
Both have 150mA at start and then down to around 40mA, with 12v.
If i connect one circit to ether the power circuit/relay or to the ignition circuit/relay it works fine.
But as soon as I connect both of them (as the diagram) at the same time all hell breaks loose. Ether nothing works, or the bike starts right away or only the ignition works etc etc. Everything but correct. It feels like the ground to the Arduino/ESP32 is the issue, but I dont know how to solve it any other way.

I start to get crazy with this now and have searched for days, but I cant find a simular problem. Please have understanding with my bad diagram but I try as good as I can.
First of all, we see no power connection to the arduino board, and next the "ground" symbols imply that all of those points are tird with a zero-resistance connection that also ties to the power source common with a zero resistance connection. And exactly what the problem is has not been adequately described.

With both a spark coil ignition device and a fuel pump, there whole LOT of electrical noise on most of the conductors. AND if the LEDs are actually lighting then the circuit is not accurate in where they are connected.
 

Reloadron

Joined Jan 15, 2015
5,117
But as soon as I connect both of them (as the diagram) at the same time all hell breaks loose. Ether nothing works, or the bike starts right away or only the ignition works etc etc. Everything but correct. It feels like the ground to the Arduino/ESP32 is the issue, but I dont know how to solve it any other way.

I start to get crazy with this now and have searched for days, but I cant find a simular problem. Please have understanding with my bad diagram but I try as good as I can.
Here's a big part of the problem. Your little sketch while not really all that good shows none of the interface between the Arduino and ESP32 module or any of the code you are using. That combined with we can't see the interface between the relays and the bike's internal wiring leaving us with a blank as to what should happen, when it should happen and why you are seeing the symptoms you are seeing.

While I have no desire to do so if I were to add a remote ignition and start to my own bike I would likely just use a 4 Channel remote relay card like this one or similar. One relay setup as latching for ignition and lights and one relay momentary for the starter function. The relay cards are inexpensive (under $20 USD) and easy to install on a 12 volt bike electrical system.

Just My Take....
Ron
 
Top