C4 - DS4 Owners :: Forums :: C4 Picasso and Grand Picasso - PRE 2013 only :: C4 Picasso and Grand Picasso General questions |
<< Previous thread | Next thread >>
|
Part names confusion |
Please Register to enjoy additional Member Benefits |
Top Thanked Forum Posts: Today | Week | Month | Year | All time | Most Thanks Given: To member | By user
|
Author | Post | ||||
she2656 |
|
||||
Member No: #55564
Joined: Feb 07 2020Location: Notts |
Please can anyone tell me if the following are one & the same item? *Voltage Retention Unit *Battery Protection Management Unit I have a battery drainage problem with a Grand C4 Picasso 15 reg. A local "Citroen specialist" replaced the former (VRU) which didn't solve the problem so I've now had it at a "main dealer" who claim it needs the latter (BPMU) replaced. Neither can/will provide part numbers. The main dealer claims there is no way of seeing which part was changed less than 3 months ago (2 of which it has spent sat in their workshop)! |
||||
|
|||||
BigJohnD |
|
||||
Member No: #82
Joined: Jan 22 2007Location: Hoylake |
AFAIK they are not the same. The Voltage Retention Unit is part of the Stop/Start system. I believe early Citroen systems used a massive capacitor (>8F) to hold power and then turn the alternator and its linked belt to turn and start to the engine. This system did not use the car's conventional starter motor. The Battery charge status control unit is very complex but primarily is there to protect the battery and prevent unnecessary discharging. |
||||
|
|
||||
|
|||||
vexorg |
|
||||
Member No: #48843
Joined: Jul 06 2017Location: Scotland |
What voltage is it retaining, even 8F is not enough to hold much in terms of car needs | ||||
|
|
||||
BigJohnD |
|
||||
Member No: #82
Joined: Jan 22 2007Location: Hoylake |
I've no idea, probably 12V to turn the alternator/starter like on a motorbike. The capacitor has a huge capacity, measured in Farads, maybe as much as 150, and a control unit to manage use and charging. There's loads for sale on EBay. Try part number 9801739380. |
||||
|
|
||||
User Colour Key: Head Administrator, Administrator, Forum Moderator, Forum Moderator, Premier Member, Technical Expert, New C4 and DS4 Forum Moderators, Member |