T350 fuel pump relay timing

[non_linear]

Hi
I'm having an intermittent problem when starting. I'd appreciate any thoughts people have.

Normal start sequence is ignition on, press immobiliser and then fuel pump runs for a couple of seconds then stops, start car.
Occasionally I am getting ignition on, and fuel pumps immediately runs constantly, press immobiliser and car will not start.

My first thought is to check the fuel pump relay, but I can't find it! There is an empty socket on the fuse board where all the drawings say it should be.
Could someone explain where the relay is, and how the timing works. Presumably there must be a signal from the management system to turn the pump back on once the engine is running.

thanks
Stuart

[Penelope Stopit]

Yes, ECU controls priming and run

Don't know if any of this helps, from a job in the past, fuel pump relay should be brown and have a diode in series with the coil, fits at the cut off corner position

Problem with job in the past was that the diode was stopping the relay from energising due to the fuse-box being incorrectly wired



Page 86 Fusebox Connector D See Pin 4.5 Green&Yellow Steering Pump Drive

Page 89 Fusebox Connector O See Pin 1.5 Yellow&Black Fuel Pump 1 DRV Rear Harness

Page 89 Fusebox Connector O See Pin 2.4 Yellow&Black Fuel Pump Relay DRV



Can post bigger images to a different image host if need be

Edited by Penelope Stopit on Tuesday 8th September 14:49

[Penelope Stopit]

[non_linear]

Many thanks, that is very useful.

So the brown relay is the one to check. I had to replace the yellow relay marked 0809 when I first got the car as it was completely rusted inside. I'm hoping that is also the problem here, as it's an easy fix. I probably should have replaced all the relays at the same time.

I'll report back!

cheers
Stuart

[Penelope Stopit]

non_linear said:

Many thanks, that is very useful.

So the brown relay is the one to check. I had to replace the yellow relay marked 0809 when I first got the car as it was completely rusted inside. I'm hoping that is also the problem here, as it's an easy fix. I probably should have replaced all the relays at the same time.

I'll report back!

cheers
Stuart

Lovely, you've found it

Hope it's a relay fault

Yes, as you comment a relay is an easy fix

Will attempt to help if you get stuck on something

[non_linear]

So it looks like corrosion on the armature has caused the contact gap to increase leading to intermittent operation.
I really do need to look at all the other relays.

As at least two of the relays have seen significant water ingress at some point is it likely the fuse board will be affected?
Anything I can do to mitigate that?

cheers

[Penelope Stopit]

It's worth taking a good look inside the fuse-box and clean it up if needed

Obviously find where the water is coming from

The fuse-box is built in layers

See an image here https://www.pistonheads.com/gassing/topic.asp?h=0&...

You could try contacting martin996uk

His box was in and out more than once

[Gladers01]

non_linear said:

So it looks like corrosion on the armature has caused the contact gap to increase leading to intermittent operation.
I really do need to look at all the other relays.

As at least two of the relays have seen significant water ingress at some point is it likely the fuse board will be affected?
Anything I can do to mitigate that?

cheers

Sounds like your fuel relay is getting stuck on intermittently, I had a poorly fitted windscreen that leaked causing the fuse box/relays to become damp, had a new screen fitted, used a hair dryer to remove the moisture and now drier than a nuns letterbox.

Interesting to note the brown fuel pump relay is a 2 pole version (2 contacts) which can drive 2 seperate circuits (compared to the yellow relays which are single pole, 1 contact) presumably to drive 2 fuel pumps ?

Good Luck, post back later if you have more info

[non_linear]

Thank you both.
It hasn't been wet during my ownership which is getting on for 3 years now, so I imagine any water is long gone.
I'm curious to know if there is likely to be long term damage due to corrosion, as I am seeing with the relays, which are now failing years after the event.
I'd prefer not to take the fuseboard out if I can avoid it, as it looks like it will be a total pain.

I'm hoping the problem was the relay sticking. Good weather for the next few weeks so I'll soon find out.

[Penelope Stopit]

If you don't want to take the fuse-box out, all you can do is let it roll and hope for no other problems in the future

You could take a look at a few plugs/sockets here and there, split them and check for corrosion

[Adrian@]

I have been looking at the 5 pin brown relay for the two pump system in use on my Tamora, which I had not looked at until now...I had read the post previously, not having pulled the relay out until today, but expecting it to be the Bosch (with the doide as described earlier in the thread), BUT, no, this is a Tyco V23134-m52-x186. Listed as M0509 ...I just thought that this should be mentioned. A@

Edited by Adrian@ on Tuesday 15th November 16:42

[mk1fan]

Racetech's replacement 5-pin relays are Tyco items.

If I understand correctly, Bosch have discontinued the relay so they are [very] hard to find new. I picked up a couple from Land Rover breakers as they are used in lots of TVR models - my 350i for starters. It is an odd relay in that both the 87 are switched to live rather than only one of them.

[Adrian@]

mk1fan said:

Racetech's replacement 5-pin relays are Tyco items.

If I understand correctly, Bosch have discontinued the relay so they are [very] hard to find new. I picked up a couple from Land Rover breakers as they are used in lots of TVR models - my 350i for starters. It is an odd relay in that both the 87 are switched to live rather than only one of them.

Stewart, did you mean to say that you understand that the 'Tyco' (not Bosch) relay has been discontinued...and Racetech's replacement is different Tyco part number. Because I can only see second hand tyco v23134-m52-x186 (I have not spoken to Xparts about what they are selling as M0509 yet (I am in at Power's tomorrow so will ask the Q. there too).
As I said, it was my bad assumption that the brown relay was the standard Bosch brown diode relay, and that PS wrongly quotes it in the thread above. (I still need to understand the wiring and the method the inertia is wired..I will get there!). I only pulled the relay out today to double check the part number as it it the last thing on the fuel delivery to change. A@

[non_linear]

I believe the tyco part is the same as SIEMENS V23134-M52-X186, which is the OEM Land Rover AMR 1088. 2 parts available on ebay at the moment.
It's been a while but I'm pretty certain the relay I pulled out did not have a series diode fitted.

Edited by non_linear on Tuesday 15th November 23:35

[Adrian@]

non_linear said:

I believe the tyco part is the same as SIEMENS V23134-M52-X186, which is the OEM Land Rover AMR 1088. 2 parts available on ebay at the moment.
It's been a while but I'm pretty certain the relay I pulled out did not have a series diode fitted.

Yes to the Seimens/Tyco, and not sure on the diode (I would need to see a pictorial). I have not looked at the wiring and how the two coil/contacts are operating (it does not help that when you read through threads the Bosch diode relay is pushed as the right relay by someone who does not own a TVR regardless of owners trying to correct him) and two normally open contacts (if I am understanding it correctly) with a 5 seconds pulse/priming the pump from the ECU energises one coil, and the second pulls in for engine run.
I have NOT looked at this any more than noting that the relay is 100% duty cycle (and my car is a 22k, nearly 20 years old, I want to replace it as part of my servicing, I would rather buy into new rather than used). A@

I hasten to add, that this does not relate to the (early Tamora/Tuscan) 6 pin relay and or the single pump Sagaris (I am working on my 2003 Tamora).

Listed here is the PDF for the Tyco. https://pdf1.alldatasheet.com/datasheet-pdf/view/5... and understanding this then needs to be related to what ever part number is being sold at traders

Edited by Adrian@ on Wednesday 16th November 09:27

[non_linear]

There is only one coil in this relay. The specs are here:

https://www.te.com/commerce/DocumentDelivery/DDECo...

The "M" in the part number designates the contact arrangement as DNO 1 form, 2NO

Edited by non_linear on Wednesday 16th November 09:47

[Adrian@]

non_linear said:

There is only one coil in this relay. The specs are here:

https://www.te.com/commerce/DocumentDelivery/DDECo...

The "M" in the part number designates the contact arrangement as DNO 1 form, 2NO

Edited by non_linear on Wednesday 16th November 09:47

Brilliant...then yes, single coil DNOR (I have now seen a pictorial on a Siemens relay with a resistor AND on your Tyco image in the thread) Does that seem right to you. (I am sat on my phone). A@

Edited by Adrian@ on Wednesday 16th November 10:18

[mk1fan]

Adrian@ said:

mk1fan said:

Racetech's replacement 5-pin relays are Tyco items.

If I understand correctly, Bosch have discontinued the relay so they are [very] hard to find new. I picked up a couple from Land Rover breakers as they are used in lots of TVR models - my 350i for starters. It is an odd relay in that both the 87 are switched to live rather than only one of them.

Stewart, did you mean to say that you understand that the 'Tyco' (not Bosch) relay has been discontinued...and Racetech's replacement is different Tyco part number. Because I can only see second hand tyco v23134-m52-x186 (I have not spoken to Xparts about what they are selling as M0509 yet (I am in at Power's tomorrow so will ask the Q. there too).
As I said, it was my bad assumption that the brown relay was the standard Bosch brown diode relay, and that PS wrongly quotes it in the thread above. (I still need to understand the wiring and the method the inertia is wired..I will get there!). I only pulled the relay out today to double check the part number as it it the last thing on the fuel delivery to change. A@

Racetech's replacement 5-pin relays are Tyco items. I am not aware - well haven't looked - if these are discontinued.

My searching to date indicate that the Bosch relays are discontinued even though they seem commonly used. Siemans versions appear [to me] to be rebranded Bosch items (or it could be vice versa ) are also discontinued.

[Adrian@]

Stewart, my problem is that I am not seeing a Bosch equivalent v23134-m52-x186 relay anywhere.

M0124 (Bosch)


M0509 (Tyco/Siemens)


A@

Edited by Adrian@ on Wednesday 16th November 12:55

[mk1fan]

https://www.racetechdirect.co.uk/car-parts/electri...

I bought these during my fuel pump issues saga just in case all four of my factory Bosch ones were faulty (two from the cars and two bought as a spare for in each car).

My existing relays were fine - the in tank wiring wasn't - and I didn't try the new ones. Happy to try them out on Saturday during my drive and get back to you.