Code 26 and no check light
Discussion
Hi Gareth,
It's possible that you missed the check engine light when the code first appeared...the ECU will store fault codes for x number of starts, 50 I believe. I assume you used something like Freescan to find the code. If the code still exists, I would perform the manual ECU code readout via the check engine light. It involves jumpering a pair of pins (not sure which two at the moment, someone will likely chime in or you can search this site or Lotus Esprit World to find them) and turn the engine on without starting it. The ECU should flash out the error code on the check engine light. This way you can see if the ECU can drive the light.
regards,
Bill
'95 S4S
It's possible that you missed the check engine light when the code first appeared...the ECU will store fault codes for x number of starts, 50 I believe. I assume you used something like Freescan to find the code. If the code still exists, I would perform the manual ECU code readout via the check engine light. It involves jumpering a pair of pins (not sure which two at the moment, someone will likely chime in or you can search this site or Lotus Esprit World to find them) and turn the engine on without starting it. The ECU should flash out the error code on the check engine light. This way you can see if the ECU can drive the light.
regards,
Bill
'95 S4S
Hi,
You can check your CEL very easily. Just turn on the ignition and you should see the CEL lights burning ... the yellow one in the dash and the green one in the relays-box. When you start the engine (and no error codes are present) both lights will go away ...
Cheers
Marcus (www.PUKesprit.de)
You can check your CEL very easily. Just turn on the ignition and you should see the CEL lights burning ... the yellow one in the dash and the green one in the relays-box. When you start the engine (and no error codes are present) both lights will go away ...
Cheers
Marcus (www.PUKesprit.de)
Yea, no check lights at all.
I guess that the ECM provides a negative to the check lights when you turn on the ignition or if a fault is found when the engine is running.
A positive feed is supplied to the other side of the bulbs through binnacle splice 'A'' and also from the RPM relay (for the rear check light).
If I attach a ground directly to the pin at the ECM plug then I can illuminate the lights but the ECM itself is not providing a ground.
Also, I've got restricted boost etc... I guess because of the code 26?
Is the lack of a correct circuit causing the code 26?
??
I guess that the ECM provides a negative to the check lights when you turn on the ignition or if a fault is found when the engine is running.
A positive feed is supplied to the other side of the bulbs through binnacle splice 'A'' and also from the RPM relay (for the rear check light).
If I attach a ground directly to the pin at the ECM plug then I can illuminate the lights but the ECM itself is not providing a ground.
Also, I've got restricted boost etc... I guess because of the code 26?
Is the lack of a correct circuit causing the code 26?
??
Hmmmmm ... looks like you have a fault inside the ECU or in the connectors. If its in the ECU its very likely that either the driver-transistor and/or the shunt-resistor is defective.
Maybe you should try replacing the ECU.
Cheers
Marcus (www.PUKesprit.de)
PS: If you need a good used ECU, please drop me a line.
Maybe you should try replacing the ECU.
Cheers
Marcus (www.PUKesprit.de)
PS: If you need a good used ECU, please drop me a line.
Thanks to all for the comments.
I am quite sure that it's the ECM so now I have contacted a place in the US and am just waiting for a price. But I'm having a little trouble getting an actual price for freight even though I have given them delivery details. Hopefully I will get an actual price soon. ECM on it's own is only $150(usd) and last time I got one in the UK it was £180(ukp) so its quite a difference.
If I don't have any joy with the guy in the US then I was planning to get another reconditioned one from South West Lotus (same place as before). Spoke to them yesterday and they still have in stock.
John, I would be interested in seeing the internal wiring diagrams, are they something you can easily distribute?
Danny, where abouts in the UK are you now?
I'm still Manchester 1/2 the time and Windsor the rest... would take you up on the offer but this time I'm 99% sure it's the ECM.
Gareth
I am quite sure that it's the ECM so now I have contacted a place in the US and am just waiting for a price. But I'm having a little trouble getting an actual price for freight even though I have given them delivery details. Hopefully I will get an actual price soon. ECM on it's own is only $150(usd) and last time I got one in the UK it was £180(ukp) so its quite a difference.
If I don't have any joy with the guy in the US then I was planning to get another reconditioned one from South West Lotus (same place as before). Spoke to them yesterday and they still have in stock.
John, I would be interested in seeing the internal wiring diagrams, are they something you can easily distribute?
Danny, where abouts in the UK are you now?
I'm still Manchester 1/2 the time and Windsor the rest... would take you up on the offer but this time I'm 99% sure it's the ECM.
Gareth
Gareth, I am working locally at the moment and am available every weekend. I have a spare ECU that is serviceable - nothing wrong with it at all. I bought it when I was trying to diagnose my fault. I will not be on the internet for a few days so contact me on my mobile - (07787) 180976. I would contact you but I have lost your mobile number.
Danny.
Danny.
Hi People
Ok - I think I was wrong about the ECM, to cut a long story short the new one is the same
Now I'm thinking that its either a bad connection between the multiplug and the ECM or (more likely) I may have put the check light cable into the wrong terminal in the plug
Stupid!!! I removed a wire from a plug the other week because it was not seating properly, I tidied it up and put it back and car seamed fine. But I didn't try it on the road and I could not say for sure that the check light came on with the ignition – I think it's a real possiblilty that it was the check light wire!!
Does anyone have a pin diagaram or something that tells me which pin the ECM light should be connected to?
Ok - I think I was wrong about the ECM, to cut a long story short the new one is the same
Now I'm thinking that its either a bad connection between the multiplug and the ECM or (more likely) I may have put the check light cable into the wrong terminal in the plug
Stupid!!! I removed a wire from a plug the other week because it was not seating properly, I tidied it up and put it back and car seamed fine. But I didn't try it on the road and I could not say for sure that the check light came on with the ignition – I think it's a real possiblilty that it was the check light wire!! Does anyone have a pin diagaram or something that tells me which pin the ECM light should be connected to?
Hi Gareth,
Look into the workshop manual section EMH.4 page 4-10. There you will find everything you need.
If you like I can send you the pages from the workshop manual, where you can see the ECM layout with wire colors and pin location.
Cheers
Marcus (www.PUKesprit.de)
Look into the workshop manual section EMH.4 page 4-10. There you will find everything you need.
If you like I can send you the pages from the workshop manual, where you can see the ECM layout with wire colors and pin location.
Cheers
Marcus (www.PUKesprit.de)
Hi decee,
Code 26 is the "quad driver circuit" fault code. Actually it stands for 9 different possible faults. If one or more of them shows a fault longer than 20 seconds code 26 is set. Possible faults are:
- rpm-relays (B)
- radiator fans (A)
- A/C control relay (B)
- engine overheat relay (B)
- throttle jack relay (B)
- wastegate solenoid (A)
- canister purge solenoid (A)
- Check engine lights (A)
- secondary injectors and/or corresponding ballast resistor (B)
In your special situation I would suspect "wastegate solenoid" and/or secondary injectors, because these are only energized when you accelerate ...
Cheers
Marcus(www.PUKesprit.de)
Code 26 is the "quad driver circuit" fault code. Actually it stands for 9 different possible faults. If one or more of them shows a fault longer than 20 seconds code 26 is set. Possible faults are:
- rpm-relays (B)
- radiator fans (A)
- A/C control relay (B)
- engine overheat relay (B)
- throttle jack relay (B)
- wastegate solenoid (A)
- canister purge solenoid (A)
- Check engine lights (A)
- secondary injectors and/or corresponding ballast resistor (B)
In your special situation I would suspect "wastegate solenoid" and/or secondary injectors, because these are only energized when you accelerate ...
Cheers
Marcus(www.PUKesprit.de)
Thanks for the information!
Does anyone know of a way to trick the ECM into acknowleging a false signal for a Relay that was not installed?
The reason that I'm asking is that the code 26 is on an S4 motor that was retro'd into an 86.
I chose to retro some of the relays over to the Delco system (signal triggers relay, relay triggers function), but with afew controls, such as Air Conditioning, I kept them as designed in the Bosch system (signal triggers function).
Now I'm wondering if I should try to produce a Phantom Signal to the ECM in order to cancel out the code 26 or retro the Air Conditioning so that the ECM is in control of it and hopefully find it was the problem.
Does anyone know of a way to trick the ECM into acknowleging a false signal for a Relay that was not installed?
The reason that I'm asking is that the code 26 is on an S4 motor that was retro'd into an 86.
I chose to retro some of the relays over to the Delco system (signal triggers relay, relay triggers function), but with afew controls, such as Air Conditioning, I kept them as designed in the Bosch system (signal triggers function).
Now I'm wondering if I should try to produce a Phantom Signal to the ECM in order to cancel out the code 26 or retro the Air Conditioning so that the ECM is in control of it and hopefully find it was the problem.
Hi Deecee,
Its not difficult to simulate the relays. Just take a 50 Ohm resitor and put it in instead of the relay-coil. This will tell/fool the ECM that the relay is there ;o)
Cheers
Marcus (www.PUKesprit.de)
Its not difficult to simulate the relays. Just take a 50 Ohm resitor and put it in instead of the relay-coil. This will tell/fool the ECM that the relay is there ;o)
Cheers
Marcus (www.PUKesprit.de)
Hey Guys
Just wanted to thank you for the help. It turned out that I had put the Check light wire to the wrong pin (7 instead of 1). It's all sorted out now! Could finally try the car under full boost since fitting new Fuel the new fuel Pump and regulator - it's great
I even drove it back from Manchester last night and will use it in London for the next few days.
Cheers!
Gareth
Just wanted to thank you for the help. It turned out that I had put the Check light wire to the wrong pin (7 instead of 1). It's all sorted out now! Could finally try the car under full boost since fitting new Fuel the new fuel Pump and regulator - it's great
I even drove it back from Manchester last night and will use it in London for the next few days.
Cheers!
Gareth
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