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* Acme Super Moderator * ** The Enforcer **
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Elise Parts sells the MFRUs.
The EliseShop ones are cheaper, but seems to suggest Rover and toyota are different, and I thought they were the same.
Mike will surely know??

A roachclip (or whatever they are called in the electrical term) if what you would need to power the solenoid as Mike mentioned, So a roachclip on a wire.
Alligator clip.

San
 

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Discussion Starter #64
Elise Parts sells the MFRUs.
The EliseShop ones are cheaper, but seems to suggest Rover and toyota are different, and I thought they were the same.
Mike will surely know??

A roachclip (or whatever they are called in the electrical term) if what you would need to power the solenoid as Mike mentioned, So a roachclip on a wire.
Thanks man, I went ahead and took your advice and ordered a new one from the place you suggested, should be here in about 3 days....damn pound to dollar conversion......
 

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Thanks man, I went ahead and took your advice and ordered a new one from the place you suggested, should be here in about 3 days....damn pound to dollar conversion......
I was about ready to send you my spare.
(I have a spare because they are common and known issue)
At some point someone in WA-state should have a spare to have buddy-up spare parts bin.


Ok so I got the MFRU off and the resistance across the far top right and far right middle pins is dead, 0.0 ohms. Does this mean that the solenoid relay is bad? I hope I am at the end of this! THanks guys
The zero ohms is a short. Open circuit is infinite or MegaOhms.
dead can be either zero (shirt) or open.
If I recall correctly there are diodes from back EMF.
If/when they short, then the MFRU doesn't work.
Since there are 4 relays in there, you can have 3 parts working and one failed... Hence a spare can be handy.
 

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Discussion Starter #66
I was about ready to send you my spare.
(I have a spare because they are common and known issue)
At some point someone in WA-state should have a spare to have buddy-up spare parts bin.




The zero ohms is a short. Open circuit is infinite or MegaOhms.
dead can be either zero (shirt) or open.
If I recall correctly there are diodes from back EMF.
If/when they short, then the MFRU doesn't work.
Since there are 4 relays in there, you can have 3 parts working and one failed... Hence a spare can be handy.
Oh it certainly is a short! I opened up the old MFRU to take a look and the conductors running from the pins to the coil were completely brown. The back of the board was brown at the solder as well, almost like Coke was spilled on it and dried up. Thanks again for your help man, I never would have come to this, there are so many electronic components in cars these days.
 

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Discussion Starter #67
Alright so the new MFRU is in place, but still no start, not even a sign of the solenoid hitting just like before. I checked the battery and volt is at 12.17 so pretty low, but it would not start on the 50 amp jumper either. I am slow charging at 2amps for a few hours to see what happens, but any other idea? Seriously afraid I just tossed 120 bucks down the drain for this part.
 

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Did you verify 12V at the harness where it plugs into the MFRU when the start button is pushed? That was one of the last checks I recommended (mentioned you might need an assistant to execute). With no voltage there the issue could be immobilizer related. If there is voltage being delivered from the harness on the pin I referenced in my earlier post when the starter button is pressed then there is a lack of a proper ground source which would be in this case the ECU.
Not to worry on the MFRU, good spare part to have on hand as sooner or later you will need it.
 

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Discussion Starter #69
Did you verify 12V at the harness where it plugs into the MFRU when the start button is pushed? That was one of the last checks I recommended (mentioned you might need an assistant to execute). With no voltage there the issue could be immobilizer related. If there is voltage being delivered from the harness on the pin I referenced in my earlier post when the starter button is pressed then there is a lack of a proper ground source which would be in this case the ECU.
Not to worry on the MFRU, good spare part to have on hand as sooner or later you will need it.
I thought the immobilizer would knock out the fuel pump as well? If not it is a pretty worthless unit as the 2k lb car can be push started relatively easily at about 4mph. I really hope this is not my ecu..........
 

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You would think that the fuel pump wouldn't come on either if it was the immobilizer, just trying to cover all the bases..
If it were me and it came down to the ecu being the issue I would bypass the ecu and ground that leg of the circuit. Just don't push the start button after the engine is running as you will get that awful starter "crunch" you get on any older car that doesn't have the fancy disconnect.
 

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Discussion Starter #71
You would think that the fuel pump wouldn't come on either if it was the immobilizer, just trying to cover all the bases..
If it were me and it came down to the ecu being the issue I would bypass the ecu and ground that leg of the circuit. Just don't push the start button after the engine is running as you will get that awful starter "crunch" you get on any older car that doesn't have the fancy disconnect.
You are a ray of hope man, I am going to look into how to do that after I get some assistance in checking those adapter pins at the mfru. The thing that has me concerned is: What caused the mfru to have that kinda slimy brown film on the solenoid pins and the back of the board? Could this have come from somewhere else, and if so, could I be burning out my new mfru by hooking it up? I will let you know what comes from that test hopefully later today....Thanks again man, what a pain.
 

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Discussion Starter #72
ok another update. I push started the vehicle just to see if maybe the solenoid was holding it up or something and drove about 30 minutes. Brought it home, shut it down started back up 3 times. Initiated the immobilizer deactivated and the car started again....I really hope this is the end of this, maybe there is something in the ecu that needed to reset? I don't know....
 

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At this point it is sounding like maybe the MFRU was out.

I would start with a black jumper cable from the Engine to the "-" to make sure it is not the ground.

Do not throw out the dead MFRU, as I am thinking about making an MRFU tester.
 

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Discussion Starter #75
At this point it is sounding like maybe the MFRU was out.

I would start with a black jumper cable from the Engine to the "-" to make sure it is not the ground.

Do not throw out the dead MFRU, as I am thinking about making an MRFU tester.
Only down side is the car is still not starting. Maybe the mfru was bad but seems something else was the culprit in shorting it out...I am chasing ground right now because the one I thought came from the battery is actually from the chasis to a grounding block and from the ground block to the engine block. I need to find the original connection from the terminal. Done chasing wire in that tight space I need to actually find the diagram.
 

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Discussion Starter #76
Alright just wanted to let you know that checking the new MFRU the top and middle right pins still show as .0 ohms and after doing a little cleaning on the old mfru there was no damage on the components. I understand this is a part that is nice to have handy, but I do not have handy money so who mentioned that? Did I test wrong or was that just bad advice?
 

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So here is what I came away from with today. I took the old mfru and broke off the shield. I tested the cable and numbers 3 7 and 8 have a constant 12v and there is no signal coming through from the ignition pushes to the others at all. I hooked up the mfru with no shield and watched as everything came on and the fuel pump (believe it or not) engages with the immobilizer on! So I after watching what happens, the two relays above the small clip were fuel pump related, one would engage with the key turned on and one would engage with the fuel pump. The other two were dead the entire time and I did not want to press my luck by activating them to see what happened. I am thinking my immobilizer is dead? I guess that is the next step....Anyone have thoughts?
 

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Set the parking brake and take it our of gear.
Get the alligator clip and wire, and then with the MFRU out, then use the pin the Mike said goes to the solenoid... put 12V from the better there.

The solenoid should click and/or the starter should start.
If it clicks then put a another batter into the car, or put it on with jumper cables.
If it starts then it is the battery.

By bypassing the whole system of ignition, immobiliser, MFRU, then the only way for the starter not to work is the "+" 12V, or the ground is bad.
Or the starter/solenoid is bad.

Props for getting the cover off the MRFU. That is not an easy task.
 

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Discussion Starter #79
Set the parking brake and take it our of gear.
Get the alligator clip and wire, and then with the MFRU out, then use the pin the Mike said goes to the solenoid... put 12V from the better there.

The solenoid should click and/or the starter should start.
If it clicks then put a another batter into the car, or put it on with jumper cables.
If it starts then it is the battery.

By bypassing the whole system of ignition, immobiliser, MFRU, then the only way for the starter not to work is the "+" 12V, or the ground is bad.
Or the starter/solenoid is bad.

Props for getting the cover off the MRFU. That is not an easy task.
Hooked a cable from the block to the battery and nothing changed, also replaced the battery already. I am stumped if it is not the immobilizer or the ecu.
 

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So I broke down the start button out of curiosity, anyone break one of these down? I have it broken down and when the wire clip is removed from the button there is one "button" that is depressed by the start button itself and makes a that clicking noise, the other side has nothing. I tested the red wire against the black wire next to it and at first I got varying resistance, from about .2-.5 and sometimes upwards of 1.9 which seemed strange. Now the resistance is intermittent from the push button, sometimes it works sometimes not....I am wondering if this is my intermittent start problem....Anyone with any experience in this please let me know your experience. Thanks again guys, I hope this thread ends soon...
 
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