SDS C4 Replace Battery Warning
06-03-2022, 04:26 PM
#1
Super Member
Thread Starter
SDS C4 Replace Battery Warning
I tried using the C4 yesterday and it gave me a replace battery warning and the battery symbol showed no bars at all. So this the 3rd time I've replaced new, fresh batteries in two days and it keeps happening. I can put in fresh batteries and within 2-3 min it will flash the battery notice.
Any ideas if something else is wrong? Does anyone make a plug in voltage supply for the C4?
Thanks
Hary
Any ideas if something else is wrong? Does anyone make a plug in voltage supply for the C4?
Thanks
Hary
06-05-2022, 02:12 PM
#2
Super Member
My C4 has never done that, and as a result I don't even know what batts it takes. Knowing electronics as I do, and what you said, it sounds like it's not charging the batts when plugged into the OBD port. I'll make some assumptions here since you didn't say, but sounds like you're using Alkaline batts because you said replaced, not recharged. The C4 sucks down some power so it's a waste of batts. It's safe to assume it takes rechargeable batts and I'd also assume AA and no doubt NiCads because those are cheapest.
Mine draws power from the car so I assume the batts are not even needed. If I recall correctly I have a charge indicator on the screen and it's charging when connected to the car. So somewhere between your cars batt and the batts in the C4, your circuit is broken.
So I'd verify the car is providing the 12v out the OBD port, just google "OBD2 pinout" to find the wires to check. If 12v is there then I'd open up the C4 for a look-c to make sure it's getting 12v from the OBD cable. From there it might be a fuse, broken wire, bad solder connection or who knows what. I would bypass any unfixable parts and plug the 12v from the OBD cable to the batts. If all fails then I'd plug the batts to the cig lighter. I'd assume it takes 8 AA's? Maybe 10 but I doubt it. If so, 8 or 10, you can connect them directly to the car via the cig lighter. Normally it's not an issue at all to charge 8 AA NiCads with 14V with no other circuitry, but best to check current flow just in case because it's possible they may start getting hot if plugged in too long so you'd need some diodes or a resistor to throttle that current. I say diodes because you need enough current to power the C4, but not so much you heat the batts, and a resistor probably won't work unless you want to do even more wiring & soldering. Up to you, but fyi and I can help either way.
If you don't have a simple multimeter then you need one for working an a car anyway, imo. It's needed to check said voltage and current. I have several which were anywhere from free to $15, so pretty cheap and all mine have been reliable.
If/when you do get it working, Alkaline don't care much for being charged. Once or twice maybe but they degrade fast and often leak. So swap to rechargeable, preferably nickel metal hydride. If it's not 8 AA's in there let me know.
Mine draws power from the car so I assume the batts are not even needed. If I recall correctly I have a charge indicator on the screen and it's charging when connected to the car. So somewhere between your cars batt and the batts in the C4, your circuit is broken.
So I'd verify the car is providing the 12v out the OBD port, just google "OBD2 pinout" to find the wires to check. If 12v is there then I'd open up the C4 for a look-c to make sure it's getting 12v from the OBD cable. From there it might be a fuse, broken wire, bad solder connection or who knows what. I would bypass any unfixable parts and plug the 12v from the OBD cable to the batts. If all fails then I'd plug the batts to the cig lighter. I'd assume it takes 8 AA's? Maybe 10 but I doubt it. If so, 8 or 10, you can connect them directly to the car via the cig lighter. Normally it's not an issue at all to charge 8 AA NiCads with 14V with no other circuitry, but best to check current flow just in case because it's possible they may start getting hot if plugged in too long so you'd need some diodes or a resistor to throttle that current. I say diodes because you need enough current to power the C4, but not so much you heat the batts, and a resistor probably won't work unless you want to do even more wiring & soldering. Up to you, but fyi and I can help either way.
If you don't have a simple multimeter then you need one for working an a car anyway, imo. It's needed to check said voltage and current. I have several which were anywhere from free to $15, so pretty cheap and all mine have been reliable.
If/when you do get it working, Alkaline don't care much for being charged. Once or twice maybe but they degrade fast and often leak. So swap to rechargeable, preferably nickel metal hydride. If it's not 8 AA's in there let me know.
