HOW TO : fuel pump relay 1 test

Spunkysandoval · Sep 3, 2009, 02:49 PM

My hand writing is not the best, so here the steps.

Step 1. Swap relay A-27X (fuel pump relay 1) with relay A-21X (Headlight Relay high)

Step 2. Turn car on so the headlamps can be turned on low beam. Observe the headlamps to see the light pattern and identify which bulb is illuminated.

Step 3. Turn the high beams on and observe the headlamps again to see if there is any change in the bulb that is illuminated, or if there is any light at all. If there is no change and there is no light at all, the relay is bad.

*NOTE* be sure to observe the high beam state for at least a few minutes because the relay can stay on for a while and then turn off. It can also just not work at all

if there is any questions, please ask. I performed this test on my GSR and on the GSR, there is two seperate headlamps for hi/lo beam. I'm not sure how the hi/lo beam is distinguished on the HID equiped models, but I assume it comes from the projector and there wont be any light at all when the hi beams are on with a failed relay.

EDIT:

For clairity on relay position

2 Deep Motoring · Sep 3, 2009, 02:54 PM

maybe im over analyzing this but long story short... if the relay is bad, the high beam should not come on at all.. am i correct? does this apply to HID equipped head lights?

Spunkysandoval · Sep 3, 2009, 02:59 PM

Quote:

Originally Posted by 2 Deep Motoring

maybe im over analyzing this but long story short... if the relay is bad, the high beam should not come on at all.. am i correct? does this apply to HID equipped head lights?

Theoretically, you are correct. However, relay failure is not always black or white. There are grey areas. Relays can turn on and be fire for a few seconds, but then fail durring operation. Relays that that are on their way out will fail in this way. I personally observed this type of failure in my tests, both on the bench and using this method described above.

LaXGSR · Sep 3, 2009, 03:34 PM

On GSR's with HID's (SSS package), the high beam is the same bulb as the low beam, but a metal plate moves up to allow more of the beam to come out. Therefore, I'm assuming this test wouldn't work for HID GSR's unless the relay failed immediately (and not after several minutes)?

To summarize, on GSR w/SSS, when you turn on low headlamps, HIDs illuminate. When you switch to high beams, a metal plate moves out of the way - there is no change in the HID bulb illumination.

therocket · Sep 3, 2009, 05:28 PM

Quote:

Originally Posted by LaXGSR

On GSR's with HID's (SSS package), the high beam is the same bulb as the low beam, but a metal plate moves up to allow more of the beam to come out. Therefore, I'm assuming this test wouldn't work for HID GSR's unless the relay failed immediately (and not after several minutes)?

To summarize, on GSR w/SSS, when you turn on low headlamps, HIDs illuminate. When you switch to high beams, a metal plate moves out of the way - there is no change in the HID bulb illumination.

I think this is correct; so maybe the test is not good for EVOs with HIDs.

However, if it can be interesting for someone, this is the datasheet of the relay NAIS ACV31212 (in the pdf it is the Micro ISO 1A type): http://www.datasheetarchive.com/pdf-...DSA-104509.pdf

EDIT: just found also this other thread: it seems that now Mitsu suggests to use, for the fuel pump, the green relay NAIS ACM32221 (we have already 3 of them in the relay box: relays H, K, N that are throttle actuator control motor relay, injector relay, starter relay) in place of the black relay NAIS ACV31212 Attention: New relay part number from Mitsubishi

Someone can check if this is confirmed?

Guru · Sep 12, 2009, 11:26 AM

Thank you for write up. Mine went bad as well. 22,000 miles, stock fuel system. might have gone bad weeks ago, not sure since I had a bum clutch that prevented me from boosting.

chidevildog · Sep 18, 2009, 03:45 PM

thanks for the info.... i switched the high beams and fuel relay and so far mine is holding up did the quick test and so far so good...

DG Motors · Sep 29, 2009, 10:51 AM

I would like to say this got a client of ours from NJ out of a huge jam today. He was experiencing some rough bucking/hesitation from 2,500rpm-5,000rpm during WOT. We have been talking through p.m to try and rectify this situation for the past week.

Today he came in and I immediately checked the FPR line that pops off from time to time and would cause this same exact dilemma.(bucking/hesitation) which is an extreme lean condition that would cause knock sums over 15+ counts during WOT

The problem was fixed and I would like to conclude by saying thank you! Client is satisfied and more so if we ever come across this problem again we will know exactly where to check!

Spunkysandoval · Sep 29, 2009, 06:35 PM

Awesome! that is exactly why I felt the need to post this quick test for people to do. I know how hard frustrating it can be when your trying to pinpoint a problem. Hopefully this will help many more people

overdrive1 · Oct 2, 2009, 02:54 PM

nice writeup....

Jimyumi · Oct 2, 2009, 04:37 PM

Quote:

Originally Posted by overdrive1

nice writeup....

+1

**macPSU** · Oct 2, 2009, 04:48 PM

So has it been confirmed that this won't work with SSS-equipped cars?

Either way, great write-up. Thanks!

19EVO86 · Oct 4, 2009, 01:22 AM

what i did was switch the fuel relay with the horn relay its the same type of relay. after they are switched honk your horn and if the horn sounds muffled then u have a bad relay

c_reber · Oct 5, 2009, 11:05 AM

Quote:

Originally Posted by 19EVO86

what i did was switch the fuel relay with the horn relay its the same type of relay. after they are switched honk your horn and if the horn sounds muffled then u have a bad relay

Nice, I have the SSS pkg and was wondering how I could test this. I'll go try it now

Spunkysandoval · Oct 5, 2009, 01:41 PM

If you try this at night with your car parked close to a flat wall where you can see the light spread pattern it will work. You have to pay close attention to the change in light patterns when you switch form low to high beam. Park your car about 10 feet from a wall and (with low light conditions of course) and toggle the hi beam to see how the light pattern changes between hi and low.

Then you can perform the test as described above.