LEXINGTON, Ohio – The questions began in early January, just weeks after IndyCar officials elected to again delay the debut of its hybrid system and do something race teams rarely – if ever – have to deal with in the midst of a championship race: Change the technical regulations and onboard a massively impactful system mid-season.

And yet there was resounding belief across the IndyCar paddock this weekend that all the bugs in the system had been fixed through 32,699 miles of testing by 31 different drivers at 10 different tracks across the country – not to mention the countless hours the systems had been run on dynos and simulators inside test facilities owned and run by Honda Racing Corp. US and Chevrolet, under conditions that were said to far exceed anything the system would experience during a race.

“Mid-Ohio will be the first race, and we’re going into it with a bit of unknown. We’ve done a lot of testing, but it is a race with 27 cars, and we’ll see what happens,” HRC US trackside engineering manager Wayne Gross said this week. “We’re pretty confident and pretty excited for it, and we’ll work through it.”

And yet, a momentary failure on the ERS inside six-time IndyCar champ Scott Dixon’s No. 9 Honda during the pace laps of Sunday’s 80-lap race at Mid-Ohio – a glitch that left Dixon’s car strapped to the back of an AMR safety team truck as the rest of the field took the green flag – marred what was an otherwise flawless weekend for the system’s coming out party.

As of Sunday evening, an IndyCar spokesperson said series officials are still “evaluating the issue” that zapped the No. 9 Honda’s Energy Storage System (the battery-like half of the ERS) of all its energy within half a lap of leaving pitlane and shut off Dixon’s Honda engine. After attempting to restart the car from the cockpit – one of the system’s unique features that had been buggy at the start of the weekend but worked Sunday – Dixon came to a stop in Turn 5 before the car was hooked onto the back of a truck and driven back to the paddock.

“It was kinda weird. There were no alarms, but when I looked down (at my dashboard) when the team said we had to go into recharge, something started discharging (the ESS) immediately at an excessive rate,” Dixon told NBC pit reporter Georgia Henneberry during the race broadcast. “It definitely isn’t a good way to start for the first time with the hybrid and not even make the warmup lap.”

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Roughly 20 minutes or so into Sunday’s race eventually won by Pato O’Ward, a litany of Chip Ganassi Racing and HRC US engineers tried plugging the ERS in to recharge it in the garages, and amazingly, the car fired back up like normal. Quickly, Dixon strapped on his helmet and HANS device, hopped back into the cockpit and rolled back out on-track 22 laps down. He ran without issue until well past the halfway point until without any other cautions, crashes or failures among the other 26 cars, there wasn’t going to be a chance for him to gain even one position in the standings and a chance to add another point or two to his total for the day. The No. 9 Honda eventually retired after completing 40 of the 80 laps and finished 27^th.

“When we got to the back straightaway and the voltage started going down, we went through all the checks and things you do if that develops, and it didn’t do anything, and with the (ESS) voltage at 0, the engine shut off,” CGR managing director Mike Hull told IndyStar after the race. “After IndyCar got the car back to us, we couldn’t find anything apparently wrong, and when we recharged the battery, and it fired up, and we ran until we stopped when we couldn’t pass anyone.

“We’ll take a look at everything this week and try to understand how that happened, but when you consider all the miles we have had in testing, we haven’t seen that happen, so it’s a little bit of a mystery to us. But we’ll get it figured out. The mysterious part is that it didn’t reoccur.”

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When asked for an explanation of what may have caused the brief failure, an HRC US representative made noted that IndyCar’s hybrid system is supplied by the series, built by Ilmor and then randomly assigned to each entry regardless of engine manufacturer affiliation.

“Our parts (the internal combustion engine) worked fine,” the Honda spokesperson said.

During an informational presentation Saturday morning with select onsite media, IndyStar asked HRC US officials if a situation such as Sunday’s might be possible – i.e., if a hybrid system failure could potentially trigger the failure of the engine.

“There are different scenarios,” explained Pierre Descamps, HRC US's head of powertrain design. “You can have a critical failure. That hopefully doesn’t happen, but it would be like an engine (totally failing). A lower-level failure could allow you to continue, and it would just be with less power.

“We’ve tested every kind of scenario on our dyno and in our labs. We can test a lot, but on-track, there’s an added factor. We tried to cover as many scenarios, but we’ll still discover new scenarios.”

It’s unclear at the moment what the investigation into the failure will entail, though HRC US president David Salters said that any parts failure in the system would lead for the entire ERS to be sent back to the factory to be thoroughly examined, with the car in question being provided a replacement. Given that Dixon’s ERS refired and ran fine the rest of the race Sunday until the car was retired, it’s unclear whether IndyCar would deem a replacement – if CGR wishes to go that route before cars are on-track at Iowa Speedway Friday – to be ‘approved’ or ‘unapproved.’ The latter, though, would induce a nine-spot grid penalty for an oval race, just like an unapproved engine change.

When asked this weekend how many backup units had already been produced and were onsite, an IndyCar spokesperson told IndyStar the number exceeded the number of backup engines for the 27-car paddock.

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After entering this weekend at Mid-Ohio, a track he’s won at six times in his career, 32 points back of Ganassi teammate Alex Palou in the title race, Dixon dropped one spot to 4^th, one point behind O’Ward (3^rd) and 71 back of Palou with eight races remaining – six of them ovals, a discipline where CGR cars have won just two of the last 12 dating back to late-2021.

When asked back in January during series Content Days about the prospect of the midseason hybrid debut having a negative impact on the championship battle, Dixon brushed off the idea that the title would – or should – have any sort of asterisk beside it, given the unprecedented rollout of IndyCar’s new technology.

“I think the process has been to make it as reliable as possible and make it really roll out in a smooth way,” he said. “I think it is what it is right now. I think it’s definitely a positive that they’re not abandoning it. I think you’ve got to do it properly in the way that they’ve done it, and I think the technology is going to be huge.

“It’s a pretty trick system and something that will hopefully evolve pretty quickly. You’ve just got to roll with it. For me, I just want a car that’s fast in whatever way you have to drive it. Sure, you could have a DNF or reliability issues maybe, but I feel like that can be true anyways with the current (engine) formula.”

Overall, IndyCar viewed the debut of its ERS that was nearly five years in the making to be a resounding success – noting that when Romain Grosjean slid off-track and spun with three laps to go, the Juncos Hollinger Racing driver successfully restarted his stalled No. 77 Chevy, eliminating the need for a full-course caution at a point in the race where it would’ve been impossible to throw a red flag and finish the race under green conditions.

“The performance of the new IndyCar hybrid power unit at Mid-Ohio Sports Car Course was impactful and highly encouraging,” the series said in a statement. “All stakeholders in the IndyCar paddock share in the pride and excitement for the future that this milestone has generated.

“It is the result of a truly unique collaboration between Chevrolet and Honda and the culmination of hundreds of hours of engineering, preparation, testing and execution. IndyCar looks forward to the continued evolution of the hybrid power unit as teams and drivers fine-tune the system to optimize performance beginning with the first use of the horsepower assist on an oval next weekend at Iowa Speedway.”

This article originally appeared on Indianapolis Star: IndyCar’s hybrid system glitch derails Scott Dixon at Mid-Ohio