Hi folks

No Start, No Communication with Battery Energy System and no communication with HVAC control module! Car was running for and went off suddenly!Ford Custom 1.0L EcoBoost PHEV, and it’s not running spanner light on and stop safely . So far, Ive checked:

 All fuses and relays  all seem fine.

12v battery replaced , Hybrid plugs and all connectors  checked from the firewall and the common fault area in the loading bay, but found no issues or corrosion.sometime ready to drive sign come on for second and go engine not run 

Tried a software update on the Battery Energy System(BECM), but it couldnt communicate to the module ,Tried to disconnect the havac control still no luck 

 

At this point, Im stuck. The only thing left might be removing the big battery or motor , but Iâm not sure if thats the right move. Also, I dont know the exact location of the Battery Energy System module.

 

Has anyone dealt with this before, or does expert  knows where the module is located? Any help would be appreciated!

 

Thanks!

Firstly as this is working on the high voltage system and due to the potential risks involved please do not carry out any work without being suitably trained/qualified.

 

As you also have AC codes in the system try disconnecting the power cables from the cabin coolant heater and AC compressor to see if the fault goes. And if they do reconnect the items one at a time to see if the fault returns.

Also the manufacturer warranty on most of the HV system is 8 years 100K.

On 2/16/2025 at 12:45 PM, gds1972 said:

Firstly as this is working on the high voltage system and due to the potential risks involved please do not carry out any work without being suitably trained/qualified.

 

As you also have AC codes in the system try disconnecting the power cables from the cabin coolant heater and AC compressor to see if the fault goes. And if they do reconnect the items one at a time to see if the fault returns.

Hi, thanks for replying. Im an auto electrician, so I know what Im doing. I unplugged the HVAC control module, which is located right below the center screen, but unplugging the AC compressor was too difficult. Ill have to remove the front end and start by disconnecting the AC motor before proceeding from there.

 

I came across another thread where someone took their car to the dealer, and it took them seven months to fix the issue. They ended up replacing the entire motor, and eventually, the dealer bought the car from them and scrapped it. There are barely any discussions about 1.0 PHEV problems, and it seems like very few people buy them due to known faults.

 

These cars were mistakenly bought from the BMS pound by owners who didnt realize they were PHEVs. However, Im going to try to fix it. If there are any experts who can help me locate the BECM module and figure out why theres no communication, i would really appreciate it.

BECM may very well be inside the HV battery case.

Be careful.

I would be tempted to take it to Ford for diagnosis, so that you know exactly what module or sensor is faulty, then fix it yourself.👍

11 hours ago, DaveT70 said:

BECM may very well be inside the HV battery case.

Be careful.

I would be tempted to take it to Ford for diagnosis, so that you know exactly what module or sensor is faulty, then fix it yourself.👍

11 hours ago, DaveT70 said:

BECM may very well be inside the HV battery case.

Be careful.

I would be tempted to take it to Ford for diagnosis, so that you know exactly what module or sensor is faulty, then fix it yourself.👍

Thanks for reply So I’m assuming it’s inside high voltage battery which’s underneath the car but not sure why same time I lost communication with hvac control module I’m along with BECM , in assuming this car water flooded 🤔the dealership will say u need to change motor after they will say higher voltage battery but yeah how much would they charge for diagnose this one 🤔