94 Fuel Relay - Defender Source
Defender Source  

Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions


Reply
 
Thread Tools
  #1  
Old August 14th, 2012, 02:45 PM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
94 Fuel Relay

I have checked the boards and still have yet to figure this one out. I love the messages that always start with, it was running fine until...

Truck overheated on a hot day (as it usually does.) Pulled over to let the fans cool it down and then it would not start. Culprit - fuel pump not running.

After checking the relays, partially dropping the tank, etc, etc, etc. I have found the following;
- Fuel pump works if I run power directly to it.
- No power being supplied INTO the fuel relay. There is a White wire with a Red strip that I think should have power to it. However there is continuity across to the blue wire with the power off.
- Inertia switch - can't find. Looked in front of shifter and on firewall. PO used to compete in rock-crawling and suspect it was removed. But don't see where.

1) Can someone tell me where the White/Red wire goes?
2) A picture of the inertia switch location in a 94.

Thanks - Living the dream of owning a Defender
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old August 14th, 2012, 03:11 PM
wcampbel@nas.edu's Avatar
wcampbel@nas.edu
Status: Offline
Bill Campbell
1994 D-90 ST
Member
 
Join Date: Jan 2005
Location: Arlington, VA
Posts: 727
Inertia switch should be directly behind the top of the fuse box. It's a red plunger looking thing.
Reply With Quote
  #3  
Old August 14th, 2012, 03:34 PM
rijosho's Avatar
rijosho
Status: Offline
Joshua
1995 Black ST - Rhinolined edition
Research Assistant/Eagle Eyes
 
Join Date: Apr 2009
Location: NYC
Posts: 16,557
Registry
Do you get door chime, dash lights, etc? Could be ignition switch glue melted - they seem to separate in extreme heat and cold. Mine happened in the dead of summer a year or two ago.
__________________
Quote:
I am talking purely from an aesthetics standpoint.
Reply With Quote
Sponsored Links
Advertisement
 
  #4  
Old August 14th, 2012, 04:22 PM
ini88's Avatar
ini88
Status: Offline
Daniel Marcello
Alloy+Grit Creative Director
Member
 
Join Date: Aug 2005
Location: Queens, NY
Posts: 2,816
I doubt it is the inertia switch unless the PO took it out and wired it up to stay off and the heat ended up breaking the connection.

Put your fingers on the two fuel relays and have someone turn the switch over to accessories and see if you can feel them click. If there is no click I would suspect your relays are dead. I can't remember which wire runs to them to supply power.
__________________
1955 Series I
1975 FC101 Vampire
1994 Defender 90 #916
1967 Lancia Fulvia
1974 Alfa Romeo GTV
Reply With Quote
  #5  
Old August 14th, 2012, 10:09 PM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
When I turn the key to accessory, I get full dash lights, head lights, etc.

There are two relays, only one will click when powered. I switch the relays, and the other relay clicks. So, I guess both relays are working.

I do not see the inertia switch above the fuse panel in the cab.

The Rave disk wiring diagram and what I am seeing at the relays does not match. Anybody have a 94 wiring diagram for this part?
I am not getting power to the relay that has the fuel pump wire coming from it.
Reply With Quote
  #6  
Old August 15th, 2012, 12:06 AM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,688
Check your chicklet. If you search you will see what I am talking about. Based on your symptoms, it seems to be the most likely culprit but I can't remember if it cuts fuel or ignition.

Cgalpin had an issue where the pump would not stay running at that was it.

Could also be the ignition switch.

My usual plan of attack is to just replace shit until I find what was wrong. Only once did I get thwarted and it was an intermittent short at the starter that was frying ignition modules (thanks to Frank the rover whisper who saw a spark in the dark on that one).

PS I am going to start asking for donations when I am correct on these, and by donations I mean you buy some of my excess rover stuff
__________________
*not legal advice*
Reply With Quote
  #7  
Old August 15th, 2012, 06:00 AM
junkyddog11's Avatar
junkyddog11
Status: Offline
oil soaked filter
95 RRC 300tdi
Member
 
Join Date: Mar 2006
Location: No. Berwick, Maine
Posts: 1,253
Ecu switches the fuel pump relay.

Ron the "chicklet" is a 6.8ohm resistor and supplies the ignition pulse to the ECU....which affects the fuel delivery but not the relay initial switching.
__________________
Matt Browne


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
new expansion complete. Not only are we the only Rover shop in Eliot Maine...now we're also the biggest.

"Dedicated to the resurrection of junk through engineering?"
Reply With Quote
  #8  
Old August 15th, 2012, 01:26 PM
evilfij's Avatar
evilfij
Status: Offline
evilfij
I have never seen a rover in person
Member
 
Join Date: Oct 2003
Location: on the internet
Posts: 14,688
Quote:
Originally Posted by junkyddog11 View Post
Ecu switches the fuel pump relay.

Ron the "chicklet" is a 6.8ohm resistor and supplies the ignition pulse to the ECU....which affects the fuel delivery but not the relay initial switching.
So probably ignition switch, wet ECU, or something in the inertia switch.
__________________
*not legal advice*
Reply With Quote
  #9  
Old August 16th, 2012, 12:03 AM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
Did some more digging and tearing things apart. Not sure what any of this means. maybe someone can chime in. In checking the harness for the fuel pump relay the White wire with Red stripe goes to the fuse panel and shows continuity with Ground. The other side of the relay harness is Blue with a Purple stripe, it goes to the ECU. Does not show continuity. Neither show power when key is on.

As you know, it gets hot on that firewall. Did the ECU bake? I am assuming that the ECU is not sending out power to the relay. Any way to test the ECU?
Reply With Quote
  #10  
Old August 16th, 2012, 06:37 AM
junkyddog11's Avatar
junkyddog11
Status: Offline
oil soaked filter
95 RRC 300tdi
Member
 
Join Date: Mar 2006
Location: No. Berwick, Maine
Posts: 1,253
White / red wire shouldn't show cont. to ground. That would be the signal to the starter relay. check the ignition switch. Did you check any of the fuses associated with the EFI?
__________________
Matt Browne


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
new expansion complete. Not only are we the only Rover shop in Eliot Maine...now we're also the biggest.

"Dedicated to the resurrection of junk through engineering?"
Reply With Quote
  #11  
Old August 16th, 2012, 07:30 AM
rijosho's Avatar
rijosho
Status: Offline
Joshua
1995 Black ST - Rhinolined edition
Research Assistant/Eagle Eyes
 
Join Date: Apr 2009
Location: NYC
Posts: 16,557
Registry
Again. Check the ignition switch.

I had a good thread on it with pics. Search the 2 words by my username.
__________________
Quote:
I am talking purely from an aesthetics standpoint.
Reply With Quote
  #12  
Old August 16th, 2012, 09:31 PM
Capt Milks's Avatar
Capt Milks
Status: Offline
Mike
Defender V-8, Defender 2.25
Member
 
Join Date: Oct 2004
Location: United States
Posts: 1,801
From the engine compartment fuse box, 20 amp, you should have a Purple/white going to the Fuel Pump relay. You also have a White/green, 20 amp, coming from the pass compartment fuse box into the relay. Going out of the relay you should have a Blue/slate going to the ECU and a White/Purple going to the Inertia switch. From the inertia switch it goes to the fuel pump also a W/P. You should have power at the relay for both the two wires going in while when it is switched you should have the power going out of the relay in the W/P to the fuel pump.
__________________
Land Rover 110
Reply With Quote
  #13  
Old January 5th, 2013, 09:02 PM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
Now that harvest is over I can direct my attention back to the 90. The latest is that I have power to both legs of the Fuel Relay(85 & 30). I have replaced the ignition switch, replaced both relays with Bosch, verified that the chicklet has 12v in and 9v out, direct power to the fuel pump when applied under the wheel well works. I then measured current across the plug for the fuel relay. It completes a circuit only momentarily when the key is first turned on from connector 30 to 87, and also the same for 85 to 86.
I am only guessing here - but it appears that the ECU is granting the grounds and then taking them away. What makes the ECU decide if it wants to shut off the fuel pump? The inertia switch is downstream of the relay. I pressed the button on the inertia switch and it is in the down position.
Reply With Quote
  #14  
Old January 6th, 2013, 04:53 AM
junkyddog11's Avatar
junkyddog11
Status: Offline
oil soaked filter
95 RRC 300tdi
Member
 
Join Date: Mar 2006
Location: No. Berwick, Maine
Posts: 1,253
The ECU "charges" the fuel system when ignition is turned on. After a few seconds if the engine is not started it shuts off.
That's all I got right now cause it's 4 am and Sunday and I'm enjoying some "couch lock" and pre ride motorcycle videos lol.

I cant remember what supplies the power when the key is in position III (cranking) but that might be an issue.......without a wiring diagram I am useless and I will not see one of those until tomorrow.
__________________
Matt Browne


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
new expansion complete. Not only are we the only Rover shop in Eliot Maine...now we're also the biggest.

"Dedicated to the resurrection of junk through engineering?"
Reply With Quote
  #15  
Old January 6th, 2013, 08:54 AM
leastonce's Avatar
leastonce
Status: Offline
Jason England
D-90 White 95 SW #65
Site Team
 
Join Date: Jul 2009
Location: NYC
Posts: 6,078
Registry
Quote:
Originally Posted by junkyddog11 View Post
The ECU "charges" the fuel system when ignition is turned on. After a few seconds if the engine is not started it shuts off.
That's all I got right now cause it's 4 am and Sunday and I'm enjoying some "couch lock" and pre ride motorcycle videos lol.

I cant remember what supplies the power when the key is in position III (cranking) but that might be an issue.......without a wiring diagram I am useless and I will not see one of those until tomorrow.
If you use the rover gauge software I think it has an option to manually trigger the relay.

I have an occasional problem in my truck that if it stalls when cold the fuel pump relay doesn't restart on subsequent attempts to start the truck.

I just turn turn the fuel pump on using my ECUmate which is similar to a rover gauge.
__________________
Quote:
Soapy water / KY jelly, etc. is is basically a must. Yes, good idea to remove trim panels - only takes 5 more minutes to do so.
Car Camping Collective founding member and Chief Executive Officer
Cat Camping Collective founding member and Chief Executive Officer
Reply With Quote
  #16  
Old January 6th, 2013, 12:55 PM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
I don't have the software you just mentioned but did do the research and will work on it this week. That looks really cool.

Based upon Junkyddog11's comment, I will also check position III on the ignition today. Thanks.
Reply With Quote
  #17  
Old January 6th, 2013, 01:10 PM
leastonce's Avatar
leastonce
Status: Offline
Jason England
D-90 White 95 SW #65
Site Team
 
Join Date: Jul 2009
Location: NYC
Posts: 6,078
Registry
Quote:
Originally Posted by Gecko View Post
I don't have the software you just mentioned but did do the research and will work on it this week. That looks really cool.

Based upon Junkyddog11's comment, I will also check position III on the ignition today. Thanks.
I think the ignition switch is available at your local part shop for about $30.
__________________
Quote:
Soapy water / KY jelly, etc. is is basically a must. Yes, good idea to remove trim panels - only takes 5 more minutes to do so.
Car Camping Collective founding member and Chief Executive Officer
Cat Camping Collective founding member and Chief Executive Officer
Reply With Quote
  #18  
Old January 6th, 2013, 06:09 PM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
I replaced the ignition switch. Still not getting any voltage at the fuel relay (30 to 87) at position III on the ignition switch. I do get a quick pulse of voltage at position II, but not enough to trigger the relay.
Reply With Quote
  #19  
Old January 6th, 2013, 06:32 PM
leastonce's Avatar
leastonce
Status: Offline
Jason England
D-90 White 95 SW #65
Site Team
 
Join Date: Jul 2009
Location: NYC
Posts: 6,078
Registry
Quote:
Originally Posted by Gecko View Post
I replaced the ignition switch. Still not getting any voltage at the fuel relay (30 to 87) at position III on the ignition switch. I do get a quick pulse of voltage at position II, but not enough to trigger the relay.
Reset your ECU?

Check the fuse ... Check by actually checking with a meter or continuity light.
__________________
Quote:
Soapy water / KY jelly, etc. is is basically a must. Yes, good idea to remove trim panels - only takes 5 more minutes to do so.
Car Camping Collective founding member and Chief Executive Officer
Cat Camping Collective founding member and Chief Executive Officer
Reply With Quote
  #20  
Old January 7th, 2013, 11:52 AM
Gecko
Status: Offline
Stefano Watson
94 D90
Member
 
Join Date: Jan 2008
Location: Sutter Creek, California
Posts: 18
I have checked all my fuses with a meter. Unplugged the ECU and reconnected.
Reply With Quote
Reply

Lower Navigation
Go Back   Defender Source > Defender & Series Technical Discussions > Defender Technical Discussions

Tags
fuel, relay

Thread Tools

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
300 Tdi Egt Q?????? Buckon37s Defender Technical Discussions 37 July 11th, 2012 11:26 AM
94 st fuel pump relay discoinjapan Defender Technical Discussions 3 February 5th, 2012 04:26 PM
Fuel pump relay 95 D90SW alaskajgg Defender Technical Discussions 32 September 18th, 2006 10:26 AM
Fuel Pump, Switch, Relay, or Wiring? bbandit Defender Technical Discussions 19 July 10th, 2005 12:08 PM
95 won't start, possible fuel priming issue? jcasteel Defender Technical Discussions 1 March 15th, 2005 09:45 AM


All times are GMT -5. The time now is 08:02 AM.


Copyright