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Suddenly happened yesterday whereby after turning on the ignition, pushing the starter button does not start the car. 2006 Elise. By towing it was able to bump start and then drive it to a local reputable garage. Quick check at the end of the day indicated no electrical signal to the starter.

Hope it just is the starter button.

Any experience by anyone else? Will be telling them today about the electrical diagrams available from the BOE Fabrication Web Site.
 

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Suddenly happened yesterday whereby after turning on the ignition, pushing the starter button does not start the car. 2006 Elise. By towing it was able to bump start and then drive it to a local reputable garage. Quick check at the end of the day indicated no electrical signal to the starter.

Hope it just is the starter button.

Any experience by anyone else? Will be telling them today about the electrical diagrams available from the BOE Fabrication Web Site.
Could be the "start relay" or the "immobilizer".
Michael
 

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Discussion Starter #3 (Edited)
Hi Michael: Thanks for the feedback. Could it be as simple as the immobilizer even though it is shutting off the flashing light, that the starter button will still not activate because of the immobilizer?
 

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Mine failed last week (starter button) on the 2005 Tapping the button repeatedly would engage the starter, pressing it would not. Changed the button and fixed the problem. Remove the two screws in the change pocket below the switches and the panel pops right out. Be careful with the angle of the two prongs on the switch when replacing it. Don't force it if it doesn't slide on easilly, adjust the angle of the prongs...Dave
 

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Hi Michael: Thanks for the feedback. Could it be as simple as the immobilizer even though it is shutting off the flashing light, that the starter button will still not activate because of the immobilizer?
If the start button is OK, then the immobilizer and the start relay are wired into the circuit. My first suspicion would be the start relay. The immobilizer disconnected the start and fuel circuits. It is possible the the start contacts in the immobilizer is defective. It is easy to check the operation of the start button with an ohm meter.
Michael
 

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Discussion Starter #6
Well the guys have been working most of the day trying to sort out the problem. Start button is OK and the Cobra imobilizer is OK since we could get the car started by towing (ie the fuel pump was working) so we could drive it to the shop.

Looks like there is some disconnect between the main module and the starter. Is there another relay hidden somewhere between as the wire colour changes (ie black wire to the starter vs coloured out of the module)? Suspect they may have to add an auxilary relay to bypass the existing system so we can get a signal to the starter.

Does any of this sound familiar?
 

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multi function relay.

jump the starter pins in the connector to bypass it and see if it starts
 

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I assume that you already checked fuse F13 and R3. You could have a broken wire somewhere or a bad connection. There are a few other areas to check as well. The starter button could be bad but I doubt it. Could be the Multi Function Relay, could be the immobilizer also. You can bypass it by removing the connector and bridging pin 5 and 12. Try to start it then. If still nothing then it is not the immobilizer.

For the starter solenoid, power goes from the battery, thru fuse F13, thru the starter button, thru the immobilizer and thru to the starter relay. That closes the relay which then flows power from fuse R3 thru the relay and to the solenoid. The starter relay gets its power from the immobilizer and the ECM

I would not assume that the immobilizer of ok because of the fuel pump working. I would still disconnect it and jump 5 and 12 to bypass is
 

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Immobilizer failure would not allow the car to be bump started. The immobilizer cuts both fuel and ignition relays if I recall correctly. Without fuel, no bump starting.
 

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Immobilizer failure would not allow the car to be bump started. The immobilizer cuts both fuel and ignition relays if I recall correctly. Without fuel, no bump starting.
Actually, yes it would. If only the immobilizer "start" relay contact failed, that is exactly what would happen.

I assume that you already checked fuse F13 and R3. You could have a broken wire somewhere or a bad connection. There are a few other areas to check as well. The starter button could be bad but I doubt it. Could be the Multi Function Relay, could be the immobilizer also. You can bypass it by removing the connector and bridging pin 5 and 12. Try to start it then. If still nothing then it is not the immobilizer.
For the starter solenoid, power goes from the battery, thru fuse F13, thru the starter button, thru the immobilizer and thru to the starter relay. That closes the relay which then flows power from fuse R3 thru the relay and to the solenoid. The starter relay gets its power from the immobilizer and the ECM
I would not assume that the immobilizer of ok because of the fuel pump working. I would still disconnect it and jump 5 and 12 to bypass is
Fuses F13 and R3 are not the problem. If F13 blew that car would not jump start and also R3 has nothing to do with the start circuit. The only fuse involved would be R2 for the immobilizer, and then the fuel pump would not work for a jump starting. However, my bet is that it is the "start" relay in the MFRU.
Michael
 

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some progress diagnosing the no start button

I figured the problem was the PFK security module since it was new in 2008 and this seemed to be a common problem after 2008. I took apart the dash, checked to make sure the button worked and checked the alarm module. Not the problem.

It now looks like the next component in the circuit is the culprit. The Engine Control Relay Unit is apparently part of the multifunction relay unit and is probably the problem. I looked around the area where the ECU is mounted and could not find anything with wires going into it except the two fuse blocks mounted above and to the left of the ECU.

It appears the multifunction relay unit was relocated because of the supercharger and intercooler tubes. Where is it?

As an aside, spending $80+ for a relay unit, especially one that is prone to failure does not make much sense. I notice the contact labels on the relay in the circuit diagram are identical to the good ol' Bosch 12 volt relay. Perhaps I will just put one of those in, once I found out where the broken relay is.

Michael
 

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Still guessed wrong!

The multifunction relay unit tests out ok. I found it by approaching the engine side of the firewall from the bottom. It is under the Engine Control Unit, about eight inches above the bottom of the car. Things are still tight but I was finally able to remove it. You have to slide a screwdriver between it and the bracket it slides on.

I unplugged the two connectors, one with large gauge wire and one with small. I removed the cover and found four Omron high current relays mounted on a printed circuit board. I traced the circuit and determined the pin outs on the two connectors. I will post them on my website when I have an extra minute.

So, I have traced the circuit and found it operational from the ignition switch, to the start switch, past the immobilser and through the Engine Control Relay Unit. That leaves only the grounding circuit from LG2 on the Engine Control Unit that comes out of the Engine Control Relay Unit at RMC2-4. (I have attached a portion of the circuit diagram.)

So I have two questions:

Can I just ground the wire coming from RMC2-4 (blue arrow)? I assume it will not damage the Engine Control Unit? (I want to avoid cutting it so as to keep things as close to stock as possible.)

(As an aside it seems like the reason the start button has a monitor from the ECU is to sense the engine is already running and therefore prevent you from pressing the start button and engaging the starter on a turning engine. I am not worried about this since most of us are already trained to not start an already running engine.)

Is the ECU covered under the extended emissions warranty? I thought I saw someone saying such on this forum. Has anyone been successful with a replacement?

I have difficulty fixing this correctly. First it is expensive, with an ECU costing above $1500, and additional labor because the supercharger plumbing needs to be disassembled to reach the ECU. Secondly, perhaps this is a weakness in the design of the T4e ECU and it will just fail again. I have seen others with this same problem but have not heard of a solution yet.

So, CharlieX or other electronics person, can I safely ground the wire or do I have to cut it so as not to affect the ECU?
 

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please ignore my previous ramblings

My starter switch has some significant problems. After many presses, the internal contacts bend and fail in such a way as to be intermittent with various resistance values, depending on a particular button push. Very strange for a two state device, on or off.

I will post a solution once I get my car back together.

Michael
 

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Final fix to unreliable start button, with pictures

Restating, the repeated button pushes would not start the car. No solenoid clicks indicating a dead or dying battery, and an occasional start.

Testing the start switch showed no problems at first. Remember this is intermittent. I got to look at the Immobiliser/Alarm, the Central Door Locking module, and the Engine Control Relay Unit (named in the latest circuit diagrams, but basically the MultiFunction Relay Unit (MFRU)). Read about my journey, see pictures of the internals, and see other information:

Lotus Exige Start Button Failure and Diagnosis

I even took apart the start switch to see what was failing. Pictures show it was binding on the case, causing varying resistance and eventually no continuity. There is a bunch of information should you want to do a keyless entry and start.

Thank you for all the help and pointers,

Michael

The Sands Mechanical Museum
 

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Michael I owe you many beers. This post probably saved me hours if not days of frustration, cursing and swearing. I had this exact problem and was preparing to go through the same excercises as you. However this post prompted me to look at the start button with a different perspective. I figured a button...WTF it works or it doesn't so thats not the culprit. Instead though this post saved me from the same path that you took. It was my button and I thank you for posting this and I am buying beers all round!
Truly appreciated!
 

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Hello,

I have an '05 Elise that won't start, everything seems normal and I suspect the switch. I am not familiar with reading wiring diagrams, could I jump some connections on the tail of the switch to see if it is infact the switch that is causing my troubles? If yes, could you help me to determine which I need to connect?

Thanks in advance,
John
 

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Hello,



I have an '05 Elise that won't start, everything seems normal and I suspect the switch. I am not familiar with reading wiring diagrams, could I jump some connections on the tail of the switch to see if it is infact the switch that is causing my troubles? If yes, could you help me to determine which I need to connect?



Thanks in advance,

John

I have a thread that covers this, in detail, with pictures on LT.
The starter mechanism crumbles on the inside. Buy a new one on eBay. Replace. Problem solved. $30.
 

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I have a thread that covers this, in detail, with pictures on LT.
The starter mechanism crumbles on the inside. Buy a new one on eBay. Replace. Problem solved. $30.
I took the mechanism apart and it looked fine inside. The button pushed the swing arm from one contact to another making a click sound. Any thoughts?
 
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