Citreon Saxo - Citreon Saxo Fuel Relay Issue

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Fri 31 May 2013 06:45
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

Hi guys, the problem I'm having is to do with my fuel pump priming on my 97, 1.1 Saxo. Currently with the Mk1 relay the pump doesn't prime, the relay clicks as it should but still nothing. So I replaced the pump and the relay to no avail... replaced the relay with two others since then to be sure. I can get the pump to run by powering it via another power source so the pumps fine and then the car will run. The wiring in the loom is all good as are the fuses... I'm absolutely stumped. I'm wondering if the relay sends a signal to the ecu and perhaps its an ecu fault? Although when I do get the car to run it runs spot on. I just can't get the origionla relay to power the pump. Any advice is greatly appreciated guys! Thanks in advance.

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Fri 31 May 2013 09:55
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Peter D

On turning the ignition on the ECU sends a signal to the relay coil to turn on the pump for about two seconds ( Prime) then when the engine is cranked the ECU sends a permanent command for the relay to power the pump. Have you checked for power at the relay, also check the connector base for the relay incase a connector has pushed back. Regards Peter

Edited by Peter D on 31/05/2013 at 09:56

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Fri 31 May 2013 16:54
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

How do I check for power at the relay without a breakout box? And what do you mean by connector base? Cheers. Lucas

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Fri 31 May 2013 17:13
Citreon Saxo - Citreon Saxo Fuel Relay Issue - jc2

Sounds like you need an auto-electrician!

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Fri 31 May 2013 17:16
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Peter D

I assume your relay plugs into a base ( That is the connector. ) If you have a meter you can probe the base to find the 12V feed with the relay out of the base connector but the ignition on and the other side of the meter on the chassis metalwork.. You can hear it click so the ECU is talking to it.

I suspect you have either blown a fuse or the Inertia cut off device and been tripped.

Red button under the bonnet, close to the windshield, nearside of the car, near the brake fluid resivoir Press to reset

Regards Peter

Edited by Peter D on 31/05/2013 at 17:21

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Fri 31 May 2013 19:58
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

I've had an auto electrician out, to the tune of 90 pounds for him to tell me I have an electrical issue. The relay and ecu are communicating, the fuses, relays working etc are all fine. Like I say I can power the pump and run the car by hardwiring it at the fusebox.

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Fri 31 May 2013 20:09
Citreon Saxo - Citreon Saxo Fuel Relay Issue - jc2

Everything that Peter D said,should have been checked by the auto-electrician;sounds like he took a lot of money to do little.

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Fri 31 May 2013 20:16
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Peter D

Have you checked the Inertia cut off device . Yes or No. Regards Peter

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Fri 31 May 2013 23:07
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

Yes sorry peter the inertia has been checked. Just to fill you in there are two different types of saxo multifunction fuel relays. A per 2000 one, aka mk1 relay and the post 2000 one aka mk2 relay... all be it they look the same they have some small differences going on inside the relay. The mk1 relay is the one for my car, that um currently having problems with. Now if I fit a mk2 one to it the pump will prime, the car will run etc but it won't turn off on the key? I'm guessing the relay is shorting somewhere along the lines and overriding the ignition switch... either way the car runs great no missing no faulty electronics etc... but it should run with a mk1 relay. Surely it running with a mk2 relay suggests wiring is fine, fuses are fine, ecu is fine, inertia is fine etc etc... I'm totally stumped.

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Fri 31 May 2013 23:16
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

As for the auto electrician his knowledge was bound by his computers capabilities, he had no real diagnostic knowledge. With the car being pre obd2 he was very limited as to what he could do. He pretended to know what he was going on about regards the cars specifics but I knew everything he was waffling. He had little knowledge of the cars wiring or ecu so I was at a loss there too... he did want nealy two hundred pounds but he ended up going away with a call out fee and his petrol money after a slightly heated exchange of words

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Sat 1 Jun 2013 11:56
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Peter D

How many pins on the MK1 and MK2 relay. Is there a diagram on the relay. Regards Peter

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Tue 9 Sep 2014 23:34
Citreon Saxo - Citreon Saxo Fuel Relay Issue - dazzaboii

Hi all Im daz, I've got into a pickle today on way back from work, I was driving around 3mins and then bam! Starts bogging then revving on its self no throttle around 2000rpm then bogged, then when Found somewhere to stop I pulled over and it cut out and would start, now I spayed fuel in to the knm filter and turned the key (at same time)and fired up straight away, so I know it's sparkin, but no fuel getting to the engin. Ive also had the classic listen for the pump and theres no sound So need to see the relay but could do with some help finding it the relay that is I'. Happy to bypass it wit. Wire to see if it works but not sur. Where it is. Thanks guys for reading

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Wed 10 Sep 2014 01:09
Citreon Saxo - Citreon Saxo Fuel Relay Issue - dazzaboii

Hi, have you tried fuel filter, u haven't mentioned it,cheap n easy to do 5mins

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Sat 1 Jun 2013 16:04
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Micky-BO

The relay on your model is what is known as a double relay has 15 pins and is either brown or black in colour. Terminal 9 on this relay goes to fuse number 9 10amp & then onto fuel pump. If you have a problem checking this out post back Hth Regards Mickeybo

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Tue 4 Jun 2013 01:20
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Lucas1

Hi guys, checked all wiring, fuses etc and all appears fine i can feed power to the pump as far back as the relay, the fuses are fine theres no loose connections and all earth points are good! Im stumped...

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Thu 11 Sep 2014 11:36
Citreon Saxo - Citreon Saxo Fuel Relay Issue - Railroad.
Not all cars have a fuel pump priming facility, and even those that do they don't always prime every time. The output of the main relay usually powers the coil of the pump relay and the ECU switches the earth to complete the fuel pump relay circuit. On some cars with Hall Effect speed sensors the ECU would not earth the pump relay if the hall sensor was stopped in a certain position. If your car starts easily and the fuel pump doesn't switch off while the engine is running I really wouldn't worry about it. My own car is a Chevrolet Kalos, and the fuel pump does not prime every time, yet it always starts on the button.
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