Relay for secondary air pump
09-19-2016, 10:36 AM
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Relay for secondary air pump
Hi guys i replace the secondary air injector pump and its not working. I can't figure out which the fuse and relay are i found the fuse diagram can someone please help
Last edited by Fenili Luca; 09-20-2016 at 12:13 PM. Reason: CA621248
09-20-2016, 12:15 PM
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09-21-2016, 12:00 PM
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09-21-2016, 03:01 PM
#6
Out Of Control!!
Also check the relay next to P. It is designated Q and is the backup relay for P
09-21-2016, 03:43 PM
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Awesome thank u so much. I really appreciate it.
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09-23-2016, 02:14 PM
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03-01-2018, 09:06 PM
#9
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I too have a general air injection code. Fuse 32 looks good, the relays are not labeled so I don’t know which one to check. Did you ever figure this out Luca? If you replaced the fuse-relay-and pump and no go then you must have a sticking valve. See if you can clean them out before replacing. Sometimes they just get gummed up.
03-01-2018, 09:26 PM
#10
MBWorld Fanatic!
did you check the left and right valves when you pulled the pump? I'm going to change my whole system because I'm on pump #2. if theres carbon build up in the 2 valves then that could cause an issue.
don't throw your old pump either you can open it up and clean out the carbon build up and it not make any noise.
don't throw your old pump either you can open it up and clean out the carbon build up and it not make any noise.
03-01-2018, 09:35 PM
#11
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did you check the left and right valves when you pulled the pump? I'm going to change my whole system because I'm on pump #2. if theres carbon build up in the 2 valves then that could cause an issue.
don't throw your old pump either you can open it up and clean out the carbon build up and it not make any noise.
don't throw your old pump either you can open it up and clean out the carbon build up and it not make any noise.
03-01-2018, 09:44 PM
#12
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well march break I'm off for a week if I get to do mine before you do yours post some pic's of how yours is looking. I have literally everything to change the whole system except new hoses. what I don't need i can return but what for sure what I'm changing is the secondary air pump, fuse, relay and air injection change over valve. if i don't have to ill leave the left and right vales alone, but it all depends on how they look once the pump is off. I'm pulling the hoses so i don't need to remove the valves and buy new gaskets and waste time if the valves don't move easily and your finger is black when you tick it inside you need to change them.
i mean I've already changed the fuse and relays once my self. the pump fuse and relay were all changed 2 years ago under warranty and it went on me again making that loud jet engine noise.
i recently found that my 40 fuse wasn't clicking in the from SAM and i think my pump is already toast, now i only get the jet whine sometimes since i fixed the fuse, its random. its defiant not cheap if i have to do this every 2 years.
i mean I've already changed the fuse and relays once my self. the pump fuse and relay were all changed 2 years ago under warranty and it went on me again making that loud jet engine noise.
i recently found that my 40 fuse wasn't clicking in the from SAM and i think my pump is already toast, now i only get the jet whine sometimes since i fixed the fuse, its random. its defiant not cheap if i have to do this every 2 years.
03-01-2018, 10:04 PM
#13
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well march break I'm off for a week if I get to do mine before you do yours post some pic's of how yours is looking. I have literally everything to change the whole system except new hoses. what I don't need i can return but what for sure what I'm changing is the secondary air pump, fuse, relay and air injection change over valve. if i don't have to ill leave the left and right vales alone, but it all depends on how they look once the pump is off. I'm pulling the hoses so i don't need to remove the valves and buy new gaskets and waste time if the valves don't move easily and your finger is black when you tick it inside you need to change them.
i mean I've already changed the fuse and relays once my self. the pump fuse and relay were all changed 2 years ago under warranty and it went on me again making that loud jet engine noise.
i recently found that my 40 fuse wasn't clicking in the from SAM and i think my pump is already toast, now i only get the jet whine sometimes since i fixed the fuse, its random. its defiant not cheap if i have to do this every 2 years.
i mean I've already changed the fuse and relays once my self. the pump fuse and relay were all changed 2 years ago under warranty and it went on me again making that loud jet engine noise.
i recently found that my 40 fuse wasn't clicking in the from SAM and i think my pump is already toast, now i only get the jet whine sometimes since i fixed the fuse, its random. its defiant not cheap if i have to do this every 2 years.
03-01-2018, 10:09 PM
#14
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the one to the left of the fuse in the yellow box, I'll add i just found this image on the net its not my SAM unit lol
03-01-2018, 10:19 PM
#15
MBWorld Fanatic!
this is what my pump sounded like when the dealer fixed it under warrant but sometime i get a very loud whine, this guy shows how much carbon is built up in the pump it should be virtually quiet.
its 100% carbon build up in the pump because its just bearings in the bottom of the pump. he blows it out with an air hose and you should see the **** that comes out of it and how quiet it is . it sounds normal like vacuums with the hoses off when he tested it.
great video!
03-01-2018, 10:27 PM
#16
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https://www.youtube.com/watch?v=zO8BvhF09aU
this is what my pump sounded like when the dealer fixed it under warrant but sometime i get a very loud whine, this guy shows how much carbon is built up in the pump it should be virtually quiet.
its 100% carbon build up in the pump because its just bearings in the bottom of the pump. he blows it out with an air hose and you should see the **** that comes out of it and how quiet it is . it sounds normal like vacuums with the hoses off when he tested it.
great video!
this is what my pump sounded like when the dealer fixed it under warrant but sometime i get a very loud whine, this guy shows how much carbon is built up in the pump it should be virtually quiet.
its 100% carbon build up in the pump because its just bearings in the bottom of the pump. he blows it out with an air hose and you should see the **** that comes out of it and how quiet it is . it sounds normal like vacuums with the hoses off when he tested it.
great video!
Maybe I should take a look at the pump in the CLK too then. If I can save it before it seizes then that’d be great.
03-01-2018, 10:33 PM
#17
MBWorld Fanatic!
hahahah i've forced myself to learn the whole system because it would cost $2000 at the dealer to fix this issue when it can possibly cost you $0-$30 with just a new relay and fuse, just by taking it apart and using an air gun lol.
if your in the states you can buy a new pump for $180US, I'm in canada it cost me $280CAD. i bought but I'm hoping to get to the pump before it seizes, i want to clean it and save it for if it happens again. I went with the Bosch pump it was much cheaper than the Mercedes OEM one and it probably is made by Bosch anyways lol. its not a hard job at all and could save you money. I need to find a place that sells RELAYS for less then the benz dealers $25CAD price.
I know ill do mine march 10th-15th when I'm on holiday. I'll post some pictures on here.
let me know how it goes!
if your in the states you can buy a new pump for $180US, I'm in canada it cost me $280CAD. i bought but I'm hoping to get to the pump before it seizes, i want to clean it and save it for if it happens again. I went with the Bosch pump it was much cheaper than the Mercedes OEM one and it probably is made by Bosch anyways lol. its not a hard job at all and could save you money. I need to find a place that sells RELAYS for less then the benz dealers $25CAD price.
I know ill do mine march 10th-15th when I'm on holiday. I'll post some pictures on here.
let me know how it goes!
03-03-2018, 05:51 PM
#18
Member
hahahah i've forced myself to learn the whole system because it would cost $2000 at the dealer to fix this issue when it can possibly cost you $0-$30 with just a new relay and fuse, just by taking it apart and using an air gun lol.
if your in the states you can buy a new pump for $180US, I'm in canada it cost me $280CAD. i bought but I'm hoping to get to the pump before it seizes, i want to clean it and save it for if it happens again. I went with the Bosch pump it was much cheaper than the Mercedes OEM one and it probably is made by Bosch anyways lol. its not a hard job at all and could save you money. I need to find a place that sells RELAYS for less then the benz dealers $25CAD price.
I know ill do mine march 10th-15th when I'm on holiday. I'll post some pictures on here.
let me know how it goes!
if your in the states you can buy a new pump for $180US, I'm in canada it cost me $280CAD. i bought but I'm hoping to get to the pump before it seizes, i want to clean it and save it for if it happens again. I went with the Bosch pump it was much cheaper than the Mercedes OEM one and it probably is made by Bosch anyways lol. its not a hard job at all and could save you money. I need to find a place that sells RELAYS for less then the benz dealers $25CAD price.
I know ill do mine march 10th-15th when I'm on holiday. I'll post some pictures on here.
let me know how it goes!
03-03-2018, 06:35 PM
#19
MBWorld Fanatic!
Pulled the pump apart on the CLK and it didn’t look terrible inside. The motor turns smooth and there was a little graphite dust but not alarming. I took a closer look at the SAM on the C and the fuse #32 actually is blown. Tested the relay for grins and it clicked happily as a fly on dog **** in July. I’m going to put in another 40A fuse and if it blows again then I’ll dig out the motor (if the windings are shorted then I’m sure it’ll have to go) and take a look at it. I don’t feel like getting on the ground and pulling the trays off to get at it right now with all the snow melting...
well thats good I hope its all fixed! I can't wait to do mine next week but until then i have to listen to the jet engine for like 40 seconds! i mean its embarrassing everyone looks and sees a mint benz making a really bad sound lol.
03-10-2018, 01:44 PM
#20
Member
Nice picture. I've been trying to find this relay for a while.
I see that port "Q" is empty, but a previous poster said it was the backup for the "P" relay. What kind of relay should be in the "Q" port? because the "P" relay does NOT fit in there. The green relay has the right "poles" (yeah, I use a lot of quotes because I don't know the proper term, sorry) that will fit in the "Q" port...
Also, My mechanic told me that the air valves can weaken over time. They can pass the initial test, but then they can fail during the 20 seconds or so that the air pump stays on causing the O2 to read that the pump isn't doing its job. just thought I'd throw that out there...
I see that port "Q" is empty, but a previous poster said it was the backup for the "P" relay. What kind of relay should be in the "Q" port? because the "P" relay does NOT fit in there. The green relay has the right "poles" (yeah, I use a lot of quotes because I don't know the proper term, sorry) that will fit in the "Q" port...
Also, My mechanic told me that the air valves can weaken over time. They can pass the initial test, but then they can fail during the 20 seconds or so that the air pump stays on causing the O2 to read that the pump isn't doing its job. just thought I'd throw that out there...
03-11-2018, 09:33 AM
#21
Member
Nice picture. I've been trying to find this relay for a while.
I see that port "Q" is empty, but a previous poster said it was the backup for the "P" relay. What kind of relay should be in the "Q" port? because the "P" relay does NOT fit in there. The green relay has the right "poles" (yeah, I use a lot of quotes because I don't know the proper term, sorry) that will fit in the "Q" port...
Also, My mechanic told me that the air valves can weaken over time. They can pass the initial test, but then they can fail during the 20 seconds or so that the air pump stays on causing the O2 to read that the pump isn't doing its job. just thought I'd throw that out there...
I see that port "Q" is empty, but a previous poster said it was the backup for the "P" relay. What kind of relay should be in the "Q" port? because the "P" relay does NOT fit in there. The green relay has the right "poles" (yeah, I use a lot of quotes because I don't know the proper term, sorry) that will fit in the "Q" port...
Also, My mechanic told me that the air valves can weaken over time. They can pass the initial test, but then they can fail during the 20 seconds or so that the air pump stays on causing the O2 to read that the pump isn't doing its job. just thought I'd throw that out there...
And it’s so true that as they get older, these systems can fail in unique and creative ways, lol. You have to go through and verify each component. My car is a 2012 with only 45,000 miles though so l lucked out and it was just the fuse. It still bugs me that the fuse blew in the first place though. Is a new pump in my future? Maybe.
And one more shout out to MBMarko for that very helpful pic! Someone should sticky this since it’s maybe the only thread on the topic with the answer posted clear as day in a photo nonetheless!
Last edited by C230Ak; 03-11-2018 at 09:35 AM. Reason: Extra content
03-11-2018, 09:50 AM
#22
MBWorld Fanatic!
No worries! I really don't want to change the left and right valves.... I hope I don't find carbon build up in them. My pump sound even worse than a week ago. I pretty much went with the None OEM route. the parts I got are the ones pelicanparts sell through a local dealer,. There all made in Germany Hella relay,Bosch pump and Peterborough switch, I will be doing the work tomorrow and can't wait to see what I find. If I need to change the left and right valves there're the only things I bought from the dealer.
I'll post some pictures if I get to opening the old pump tomorrow.
I'll post some pictures if I get to opening the old pump tomorrow.
03-11-2018, 10:05 AM
#23
MBWorld Fanatic!
Out of curiosity, what happens if you just disconnect the SAI?
I know it's just for emissions reasons that this damn thing exists..
I know it's just for emissions reasons that this damn thing exists..
03-11-2018, 10:08 AM
#24
MBWorld Fanatic!
Last time my pump failed the check engine light went on and the car showed 2 codes. I cleared the codes with my scanner and they came back after starting the car.
I should add I've read that gas milage is worse and the car can run rich. This system is ridiculous. If I could take it completely out I would lol!
If this pump fails on me again I might post a video of me blowing up my the secondary air pump with dynamite.
I should add I've read that gas milage is worse and the car can run rich. This system is ridiculous. If I could take it completely out I would lol!
If this pump fails on me again I might post a video of me blowing up my the secondary air pump with dynamite.
Last edited by MB Marko; 03-11-2018 at 10:12 AM.
03-11-2018, 10:16 AM
#25
MBWorld Fanatic!
Last time my pump failed the check engine light went on and the car showed 2 codes. I cleared the codes with my scanner and they came back after starting the car.
I should add I've read that gas milage is worse and the car can run rich. This system is ridiculous. If I could take it completely out I would lol!
If this pump fails on me again I might post a video of me blowing up my the secondary air pump with dynamite.
I should add I've read that gas milage is worse and the car can run rich. This system is ridiculous. If I could take it completely out I would lol!
If this pump fails on me again I might post a video of me blowing up my the secondary air pump with dynamite.
Totally get that a car would show codes - it's designed that way. That said, the SAP (love that acronym)
should turn off after reaching a certain temperature and/or 90 seconds has elapsed. I don't know why your gas mileage would be worse or the car would run rich because the pump is turned off.If one can live with codes, I'm fairly certain there is no harm to the vehicle if the SAP is disabled.
