We have enjoyed 15K+ miles in our 2023 Tellaro 20L since taking delivery back in July 2022. It has the ReLion 200Ah Lithium power system in the coach. Traveling in Tennessee on January 10th, we found the lithium system totally discharged. It had been fully charged and operating fine. We went on to Florida but cut the trip short, troubleshooting all along. Today, January 25th, the batteries finally came back to life and the source problem was identified. Now it is fully charged and semi-operational. This recaps the 2-week saga and findings.
Problem Symptoms and Trouble Shooting
Upon finding lithium power “dead”, the symptoms never changed over two weeks of system recovery attempts. I got great support from the Thor Sequence and Tellaro Owners and Wannabees site, especially Mark P. Walker, group expert. I also had talks with Thor (outfitter) and Mastervolt (Combi Master inverter). Here are the things I saw and did:
- No coach electrical system gauges lit up or worked except a flashing error condition from the solar controller trying to feed the system.
- All the basic fuses and breakers were good.
- The system would not take a charge from any of the three sources.
- The Mastervolt Combi Master inverter displayed the expected statuses when connected to shore power, but it was blank/non-responsive in response to the alternator (a.k.a. the âunder hood generatorâ or UHG).
- System gauges and coach lights would not come on when connected to shore power, with the exception of the Smart Remote.
- When connected to shore power (20 or 30 amp), the Smart Remote would not move beyond the âbulk chargingâ phase; in actuality, it was not charging at all.
- Under the van, the primary 50-amp fuse and the 250-amp mega fuse were verified.
- Multiple opinions were expressed that the system needed to be âwoken upâ or subjected to a âdark startâ. Fully discharged lithium batteries can “switch off”, and some brands reportedly have a battery restart switch.
I went through the above list a few times, to no avail. It was frustrating to be in Florida for the old manâs 99th birthday, a celebrated WWII fighter pilot. He is one of four surviving Hell Hawks. Qualified service centers in Florida were booked up and not close to the celebrations.
Problem Resolution
The Krenek RV Center, where I bought the rig in Coloma, Michigan, made time to work the issue. I am glad they did. They worked in concert with Thor for about six hours yesterday, the first day. They confirmed there was no voltage at the batteries. Trouble shooting and symptoms and initial results were similar to mine. At the end of the day yesterday, they put it on a last overnight charging cycle. This final attempt was anticipated to confirm the batteries were bad.
Even though the batteries again didnât charge, the Krenek technician was not ready to accept that they were bad. On the dash there is the emergency start button, which is designed to start the van off of the coach batteries in the event that the chassis battery is dead. He pushed the emergency start button, and everything lit up. The batteries immediately woke up and were able to take a charge. Once the batteries were awake, they would only charge from shore power, but not via the alternator/UHG. This indicated the UHG to be the point of failure.
Findings/Learnings
The batteries had totally discharged. On our vanâs particular version, there is no setting or switch or prescribed way of âwakingâ them. Sometimes they are known to simply start charging after appearing to go totally dead. But not always.
Hitting the emergency start button is not a prescribed way of waking the batteries. This act might have prompted or rest communications between the coach and chassis batteries. Or in fact it might have directly woken up the lithium batteries. While the coach batteries were totally discharged, it was not possible to observe that the UHG had failed. However, itâs not clear why the UHG failed or why that failure would discharge the system.
Now back in Michigan, we’re waiting for a UHG. Lithium power is fully charged (floating 100% state of charge). So, the van can again be driven with the battery bank switched off.
New batteries would not have resolved the issue. So, credit the Krenek technician for pushing on and finding the real problem.