Quad Driver Module 1 Code 26
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
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Quad Driver Module 1 Code 26
Quad Driver Module 1 Code 26
This is the code that I am getting.
Do I Need a ECU? Thats basically what everyone i have searched on the internet is telling me.
Please let me know.
If you have one I am interested if that will fix the problem.
It runs rough, and is f*ked until I replace the ECU I think.
but let me know, these things are hard to come by.
anyone?
-Brian
This is the code that I am getting.
Do I Need a ECU? Thats basically what everyone i have searched on the internet is telling me.
Please let me know.
If you have one I am interested if that will fix the problem.
It runs rough, and is f*ked until I replace the ECU I think.
but let me know, these things are hard to come by.
anyone?
-Brian
Racer
Joined: Dec 2006
Posts: 499
Likes: 27
From: shapleigh maine
Code 26 QDM 1 means the ECM has seen a shorted condition in a circuit connected to QDM 1. It is not the fault (usually) of the ECM. You must identify the shorted component in the circuit. Replacing the ECM will most likely result in the same code.
Bob
Bob
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
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Any help offered would be greatly appreciated.
Thank you in advance.
-Brian
Racer
Joined: Dec 2006
Posts: 499
Likes: 27
From: shapleigh maine
try this.
Disconnect the above solenoids one at a time and see if the condition clears. Also you can check the resistance of the when they are disconnected. One of the is shorted, or the wiring has a short.
Bob
Pro
Joined: Dec 2009
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I got mine when my Evap solenoid went belly up.
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
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Thread Starter
Heel & Toe
Joined: Aug 2009
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I went snooping around the engine, and I know where the EGR is, I dont know where the air pump is, let alone how to disconnect it.
Does you have a picture of any of these things or, possibly a map of the whole engine?
can you take a picture of what I should be disconnecting?
Thank you..
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
Likes: 0
I got mine when my Evap solenoid went belly up.
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
I cant find them.. I dont have a detailed layout to find where they are.
Thanks.
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
Don't have a picture, and most of that stuff is off the 92 race car.
Maybe this will help:
look at the drivers side of the intake.
Find the intake manifold bolts to the rear of the looped hose
One of them has a black box with 2 vaccum lines and an electricl connection.
This is the EGR selenoid.
Look at the passenger side of the intake
Find the front intake manifold bolts
one of them has a similar looking black box with 2 vaccum lines and an electrical connection.
This is the EVAP selenoid
The AIR pump is in the area under the driver front head light.
Its kinda noisy, have the hood up, start the car, get out and listen to that area. If you don't hear a high pitch whine then it is in the wiring or relays.
Please get a copy of the Factory Service Manual - it will save you tons of time and frustration.
Maybe this will help:
look at the drivers side of the intake.
Find the intake manifold bolts to the rear of the looped hose
One of them has a black box with 2 vaccum lines and an electricl connection.
This is the EGR selenoid.
Look at the passenger side of the intake
Find the front intake manifold bolts
one of them has a similar looking black box with 2 vaccum lines and an electrical connection.
This is the EVAP selenoid
The AIR pump is in the area under the driver front head light.
Its kinda noisy, have the hood up, start the car, get out and listen to that area. If you don't hear a high pitch whine then it is in the wiring or relays.
Please get a copy of the Factory Service Manual - it will save you tons of time and frustration.
Last edited by jaa1992; Jul 5, 2011 at 08:43 AM.
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
First page of DTC 26 diagnostic chart showing wiring diagram.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
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First page of DTC 26 diagnostic chart showing wiring diagram.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
First of all I would like to say thank you and I love you guys for helping me with my problem here.
I havent totally figured it out yet.. but Im working toward the resolution.
I measured the resistance of the ohms on both the EGR solonoid as well as the Canister Purge valve solonoid and they are both OL (open loop)
meaning they are both bad. I have the EGR solonoid, and I am awaiting the canister purge solonoid.. So, just for the hell of it, i measured the ohms of the new part.. to make sure im doing it correct and it comes back with a value. So, as soon as I can get the other part.. hopefully this weekend.. I will be out there trying to put these bad boys on.
thank you so far for your help and I will give you an update asap.
-Brian
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
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its been a year.
I am not able to get this car running correctly, and still need help.
I replaced the things mentioned, and still nothing.
Could this be in fact the ecm ?
On the diag sheet it is the last thing there
-Brian
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
Likes: 0
First page of DTC 26 diagnostic chart showing wiring diagram.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
Electric air pump, left front behind headlight, the relay is mounted to the cover
Air bypass solenoid behind AC compressor below ASR servo, has vacuum connection on top, wiring is below (white tab on connector)
EGR solenoid, (blue connector) under left fuel rail cover, lift straight up to remove cover.
Canister purge solenoid (red and blue connector) under right fuel rail cover
Most quad driver circuit one failures I have diagnosed are purge solenoids that fail "open", a quick check is remove the connector then take an ohm reading across the two pins of the solenoid, if it is open (infinite resistance) it is bad.
I replaced the EGR solonoid, and I think the canister purge solenoid
What now ?
ECM ?
Thread Starter
Heel & Toe
Joined: Aug 2009
Posts: 16
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I did do the diagnostic, like a year ago now (or longer)
I replaced those parts, and didnt fix the problem.
They were only like $50 for the both of them.
But,
when the mechanic had the scanner connected we got the
'quad driver ' code mentioned above, and once the car was running, he was unable to communicate with it, and everything was N/A.
In his opinion in needs a ecm.
Anyone in RI have an extra ECM, or will lend me one to test ?
Thanks,
-Brian
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
I got mine when my Evap solenoid went belly up.
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
But it is usually not a short but one of these 3 items -
1) Evap Solenoid - this would be my bet, as they are turned off and on frequently
2) Air Pump relay - real easy to check, start your engine and listen for pump.
3) EGR Solenoid
I had the same code 26 for my 94 but the solution was different. It was the solenoid…easy fix.
You got to use the right book and information to be in the right place.
Last edited by pcolt94; Jul 5, 2012 at 03:59 PM.
Thread Starter
Heel & Toe
Joined: Aug 2009
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Could this be a late 93?
No, its def. a 92, and says so based on the vin/title.
Code 26 is different for a 92 compared to a 94. On a 94 the code is the evap canister. And the 92 is the quad driver. I believe the posts relating to the quad driver for the 92 is the correct path.
I had the same code 26 for my 94 but the solution was different. It was the solenoid…easy fix.
You got to use the right book and information to be in the right place.
No, its def. a 92, and says so based on the vin/title.
Code 26 is different for a 92 compared to a 94. On a 94 the code is the evap canister. And the 92 is the quad driver. I believe the posts relating to the quad driver for the 92 is the correct path.
I had the same code 26 for my 94 but the solution was different. It was the solenoid…easy fix.
You got to use the right book and information to be in the right place.
I am going to have the mechanic look at this again.
Well used the reference material from above, and with the parts replaced, there was no change in running condition/codes.
Hence the reason, the mechanic said it is the ECM.
I just didnt want to throw $350+ at an ecm (which NO ONE stocks) to find out i am replacing something blindly, and it wont even fix the problem.
$50 isnt that bad for the thing i did replace .. (solenoids), the originals seemed old, and did nothing to fix the codes.
Also, the air pump seemed fine to me at the time.
Any suggestions from here ?
Im thinking about starting all over again, and re-trying the diagnostic.
Maybe i am the fail, but I dont think so, I tend to agree its the ecm.
When i was driving the car, on the highway during the summer, all of a sudden, i have the CELs, and it felt like ****.
My mechanic corfirmed only 1/2 the engine was firing.
-Brian
\
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
Well, as I said before, I replaced the EGR solenoid, and the canister purge solenoid.
I am going to have the mechanic look at this again.
Well used the reference material from above, and with the parts replaced, there was no change in running condition/codes.
Hence the reason, the mechanic said it is the ECM.
I just didnt want to throw $350+ at an ecm (which NO ONE stocks) to find out i am replacing something blindly, and it wont even fix the problem.
$50 isnt that bad for the thing i did replace .. (solenoids), the originals seemed old, and did nothing to fix the codes.
Also, the air pump seemed fine to me at the time.
Any suggestions from here ?
Im thinking about starting all over again, and re-trying the diagnostic.
Maybe i am the fail, but I dont think so, I tend to agree its the ecm.
When i was driving the car, on the highway during the summer, all of a sudden, i have the CELs, and it felt like ****.
My mechanic corfirmed only 1/2 the engine was firing.
-Brian
\
I am going to have the mechanic look at this again.
Well used the reference material from above, and with the parts replaced, there was no change in running condition/codes.
Hence the reason, the mechanic said it is the ECM.
I just didnt want to throw $350+ at an ecm (which NO ONE stocks) to find out i am replacing something blindly, and it wont even fix the problem.
$50 isnt that bad for the thing i did replace .. (solenoids), the originals seemed old, and did nothing to fix the codes.
Also, the air pump seemed fine to me at the time.
Any suggestions from here ?
Im thinking about starting all over again, and re-trying the diagnostic.
Maybe i am the fail, but I dont think so, I tend to agree its the ecm.
When i was driving the car, on the highway during the summer, all of a sudden, i have the CELs, and it felt like ****.
My mechanic corfirmed only 1/2 the engine was firing.
-Brian
\
In reviewing the information again I can see how with one error code (26) you could go in 4 basic different directions. Not a real dedicated error code. The ECM probably just has a quad switch in one chip.
But I still recommend the advice offered where you are going to have to isolate all inputs to find if it is the ECM or not.