Discovery I Talk about the Land Rover Discovery Series I within.

Starter motor problem

  #1  
Old 02-11-2012, 11:53 AM
johnmb's Avatar
2nd Gear
Thread Starter
Join Date: Feb 2012
Location: Bedfordshire UK
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default Starter motor problem

I have an intermittent starter circuit problem; usual thing, turn the ignition key and all you hear is a click. I at first suspected the starter motor/solenoid and therefore used a meter to look at the low current feed to the solenoid (activated by turning the ignition key). In circuit, the wire failed to exceed a fraction of a volt. Hence, the fault must be earlier in the circuit than that.

I wanted to check the starter relay (that feeds the solenoid) behind the passenger footwell panel. However, all the wiring colours were wrong as compared with the Haynes manual wiring diagram for pre 94 discos (mine is J reg 91/92). I have attached a picture of the relay positions. One thing to notice is that there seems to be two relay positions instead of one as in the diagram. The other is that someone has done a real cowboy job on it by replacing the relays with wires poked in the contacts, completely failing to see why the relays were originally there [ to protect the ignition switch from the damage of arcing current ].

Does anyone have a better wiring diagram as to what connects to where with matching wiring colours ? Is the reason that the relays are missing that the relays can't be obtained anymore ?
 
Attached Thumbnails Starter motor problem-disco_starter_relays.jpg  
  #2  
Old 02-11-2012, 12:13 PM
Savannah Buzz's Avatar
Super Moderator
Join Date: Jan 2011
Location: Savannah Georgia
Posts: 16,322
Likes: 0
Received 82 Likes on 79 Posts
Default

1. You can get that style of relay in parts stores and pull outs from junk yards, or dismantlers, pretty basic.

2. RAVE has drawings back a few years, but may not have your exact one.

3. If truck was working with this bypassed for some period of time, perhaps there are other places to look. Certainly there would be the small gauge wire leaving the starter, which is the (+) volts to activate the solenoid, which will intenally switch on the starter to the large cable to the battery, about a 300 amp drain for a brief period on the main cable. If you are note getting 12 volts to the solenoid, have to work back from there. Of course, start with clean battery lugs and terminals, and take a peek at the ground bond at the end of the (-) battey terminal cable, straight down on the frame below the radiator. And cables at and near starter. Relays may also have been part of immobilzation, but I can't say for sure. You are correct that using the light duty contacts in the ignition switch to directly control the solenoid would not last forever. You may have to clean up the wiring, and even add your own starter relay.
 
  #3  
Old 02-11-2012, 03:10 PM
Spike555's Avatar
Team Owner
Join Date: Jun 2007
Location: Grand Rapids MI
Posts: 26,212
Likes: 0
Received 95 Likes on 72 Posts
  #4  
Old 02-11-2012, 09:34 PM
Join Date: Mar 2010
Location: Pittsburgh PA suburbs.
Posts: 5,584
Likes: 0
Received 7 Likes on 7 Posts
Default

Also check your frame ground chassis connections for both battery and starter cables to chassis. Corrosion at the ends or in the cables will give you problems.
 
  #5  
Old 02-12-2012, 04:35 AM
johnmb's Avatar
2nd Gear
Thread Starter
Join Date: Feb 2012
Location: Bedfordshire UK
Posts: 2
Likes: 0
Received 0 Likes on 0 Posts
Default Next step

Let's assume for a moment that it turns out to be a burn't out contact in the key ignition rotary switch. I can do a test start by turning the switch to position 2 and then manually flashing the wire at the relay position to +12 volts.

Now having established this, for the long term, I want of course to replace the wire hacking with proper relays. However, is it practical to replace the rotary ignition switch or should I be pragmatic and wire in a separate starter switch as a switched 12 volt start signal to the starter relay (a bit like the very old mini ).
 
  #6  
Old 02-12-2012, 06:41 AM
Savannah Buzz's Avatar
Super Moderator
Join Date: Jan 2011
Location: Savannah Georgia
Posts: 16,322
Likes: 0
Received 82 Likes on 79 Posts
Default

People can and do replace the starter switch. In case the RAVE is difficult to download, here's the pages that cover starting, and color code for wires.

The relays in question might be part of starting, or might be part of another sub-group, like ignition and shift interlock. That could explain relation to starting, but colors being wrong per reference guide. The RAVE has photos of location, and connector pin outs, it is possible with Adobe to even do a search for a wire color, like UK, which would be "blue - pink", etc.
 
Attached Files
File Type: pdf
d1 start A.pdf (750.6 KB, 723 views)
File Type: pdf
d1 starter B.pdf (1.07 MB, 2308 views)
File Type: pdf
d1 color chart.pdf (144.9 KB, 403 views)

Last edited by Savannah Buzz; 02-12-2012 at 06:44 AM.
  #7  
Old 02-12-2012, 04:54 PM
JoeManly's Avatar
Overlanding
Join Date: Dec 2011
Location: Conowingo, MD
Posts: 21
Likes: 0
Received 0 Likes on 0 Posts
Default

DLS Independant Landrover Centre in the UK (01629 822 185) has a new ignition switch for 29.95 so there really is no reason not to just replace the rotary ignition switch if that's what you need.
 

Last edited by JoeManly; 02-12-2012 at 05:40 PM.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Gimebakmybulits
Discovery I
5
07-14-2014 05:57 PM
johnkbl
Discovery II
7
04-23-2012 07:49 PM
mkt
General Tech Help
6
05-23-2008 06:33 PM
hsmatharu
Defender
3
08-23-2006 12:33 AM


Thread Tools
Search this Thread
Quick Reply: Starter motor problem



All times are GMT -5. The time now is 06:40 PM.