Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > Technical Help Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 5th September 2018, 10:36   #11
RoverP480
Gets stuck in
 
None at the moment

Join Date: Jan 2018
Location: Hereford
Posts: 501
Thanks: 1
Thanked 165 Times in 146 Posts
Default

I think according to the wiring diagram I have there is a voltage sensing lead to the ECM ,White/red trace , which is there to modify output
RoverP480 is offline   Reply With Quote
Old 5th September 2018, 14:14   #12
Mickyboy
SERVICING AND DEALER DIAGNOSTICS
 
Mickyboy's Avatar
 
MG ZT CDTI 135 + & MGZT CDTI AUTO 160 & ROVER 75 TOURER CDTI 160 TROPHY YELLOW

Join Date: Aug 2013
Location: Hernebay
Posts: 4,331
Thanks: 818
Thanked 2,414 Times in 1,141 Posts
Default

Quote:
Originally Posted by COLVERT View Post
I believe you mean the in-built regulator in the alternator don't you and not the ECM.---The engine temperature has no input here.---
I’m referring to the ECM or as it’s more commonly called ECU, as the poster Rover P480 before me has stated it is voltage sensing, when the engine is cold it will attempt to put in a higher charge rate
Mick
__________________
[SIGPIC][/SIGPIC]
T4 Owner
Jobs done : new UBP, Spy hole mod, Rear hub(wheel bearing),plenum cleaned and emptied, Inline thermostat fitted,Full service, In car Digital tv/DVD Bluetooth Satnav etc, Replaced UBP, Restored headlights,Fixed airbag connection.replaced HP pump,replaced rear light seals,changed intercooler O rings.

Jobs to do: ,replace drivers lock,.
[/SIZE]
Mickyboy is offline   Reply With Quote
Old 7th September 2018, 13:37   #13
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 14,003
Thanks: 3,851
Thanked 2,167 Times in 1,816 Posts
Default

Quote:
Originally Posted by Mickyboy View Post
I’m referring to the ECM or as it’s more commonly called ECU, as the poster Rover P480 before me has stated it is voltage sensing, when the engine is cold it will attempt to put in a higher charge rate
Mick
As you say there might be a voltage sensing lead into the ECU. This could be for information needed by the ECU when starting the car.

The connections to the alternator are those direct to the battery and the earth. None to the ECU.

To make the alternator raise its charge the electrical supply to the alternator armature has to be increased. The armature is an electro magnet, the strength of which depends on the input current into it.

The output from the alternator comes from its field coils.. There is a voltage sensing circuit in the alternator regulator. When the electrical voltage in the cars electrical system rises to around 14 to 14.5 volts the regulator steps in and limits the electrical supply to the alternator armature. The magnetic strength holds steady. So does the alternator output.

There is no way that the ECU can control the supply of current to the armature. There is no circuitry to do this. Nor is it needed.---


Happy motoring.----

COLVERT is offline   Reply With Quote
Old 7th September 2018, 14:42   #14
SD1too
Doesn't do things by halves
 
SD1too's Avatar
 
Rover 75 2.5 Connoisseur Auto (1999) Dealer launch model.

Join Date: Mar 2007
Location: Former Middlesex
Posts: 20,265
Thanks: 1,587
Thanked 3,749 Times in 3,181 Posts
Default

RAVE has an explanation in which I’m sure all readers of this thread will be interested:

”A signal output is also provided by the regulator and provides output data to the Engine Control Module (ECM) which adjusts the idle speed under varying electrical loads.”

So it’s nothing to do with charging as Colvert has said. We learn something new every day don’t we!

Simon
__________________
"Whatever is rightly done, however humble, is noble."
Sir Henry Royce.
SD1too is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 18:04.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd