Sharing this in case it helps someone else.
I have a 2025 INEOS Grenadier Trialmaster, purchased in November, and I’ve been dealing with the A/C issues many of you have probably heard about:
• Rear vents blowing super hot
• One side cold-ish
• The other side ambient to warm
Over the past few months, following the service protocols the dealer replaced:
• The controller
• The valve
• The A/C box
They also:
• PicoScoped the vehicle
• Changed the coolant
• Updated software
• Reset modules
I tried all the usual suggestions too — boot-up procedures, making sure everything was off before shutdown, etc. Nothing worked.
What finally fixed it?
The dealer went full deep-dive and traced every wire. Turns out one of my ground straps, one unrelated to the A/C, wasn’t connected properly. Once that was corrected, the A/C started working exactly as it should. It was the ground strap under the seat and under the flooring.
So if you’re dealing with the same A/C symptoms and haven’t gotten a real fix yet, it might be worth having the ground straps checked before throwing more parts at it.
Hope this saves someone some time and frustration. Still love my Greeny despite this hiccup. Crossposted on other platforms so sorry if you have seen this already.
TL;DR: have the dealer check the ground straps, even those unrelated to the AC system. What fixed mine was the the ground point under the driver seat. It is a 10 mm bolt located under the flooring near the center console.
I have a 2025 INEOS Grenadier Trialmaster, purchased in November, and I’ve been dealing with the A/C issues many of you have probably heard about:
• Rear vents blowing super hot
• One side cold-ish
• The other side ambient to warm
Over the past few months, following the service protocols the dealer replaced:
• The controller
• The valve
• The A/C box
They also:
• PicoScoped the vehicle
• Changed the coolant
• Updated software
• Reset modules
I tried all the usual suggestions too — boot-up procedures, making sure everything was off before shutdown, etc. Nothing worked.
What finally fixed it?
The dealer went full deep-dive and traced every wire. Turns out one of my ground straps, one unrelated to the A/C, wasn’t connected properly. Once that was corrected, the A/C started working exactly as it should. It was the ground strap under the seat and under the flooring.
So if you’re dealing with the same A/C symptoms and haven’t gotten a real fix yet, it might be worth having the ground straps checked before throwing more parts at it.
Hope this saves someone some time and frustration. Still love my Greeny despite this hiccup. Crossposted on other platforms so sorry if you have seen this already.
TL;DR: have the dealer check the ground straps, even those unrelated to the AC system. What fixed mine was the the ground point under the driver seat. It is a 10 mm bolt located under the flooring near the center console.
