Vacuum pump relay
#2
A long and winding road
OK, the ECM controls the brake boost pump.
SHORT ANSWER:
Under the hood in the main junction box Check link 11E, fuse 24E and relay 260. In the Central junction box behind the glove box check fuse 28P, and all the wires in between. Oh, and the pump itself.
LONG ANSWER:
From the battery connector C1631 pin 1 red wire runs to C0632-1 in the under hood junction box. From there it runs thru link 11E (30 amps) to C0570-114 a brown wire to C0028-4 (ignition switch S176) When in the cranking mode it leaves C0028-7 white and red? wire to C00582-5 at the central junction box behind the glove compartment to fuse 28P (5 amps) out C0583L-35 green wire and back to the main junction box C0570-69 to one side of the relay R260 solenoid then C0570-71 green and white wire to ECM CC0635L-16 (presumably the ECM goes to ground activates the solenoid and closes the relay). ALSO from battery C1641-1 red wire to main junction box to fuse 24E (20 amps) to the switched side of relay. When closed it leaves at C0570-88 on a green wire to C2709-1 at the boost pump (M296) out on connector C2709-2 1.5 meters long black wire to a grounding lug.
Sorry for the long explanation, but these things can be frustrating when looking for a reason why they don't work properly.
Hope this helps more than confuses.
Jeff
SHORT ANSWER:
Under the hood in the main junction box Check link 11E, fuse 24E and relay 260. In the Central junction box behind the glove box check fuse 28P, and all the wires in between. Oh, and the pump itself.
LONG ANSWER:
From the battery connector C1631 pin 1 red wire runs to C0632-1 in the under hood junction box. From there it runs thru link 11E (30 amps) to C0570-114 a brown wire to C0028-4 (ignition switch S176) When in the cranking mode it leaves C0028-7 white and red? wire to C00582-5 at the central junction box behind the glove compartment to fuse 28P (5 amps) out C0583L-35 green wire and back to the main junction box C0570-69 to one side of the relay R260 solenoid then C0570-71 green and white wire to ECM CC0635L-16 (presumably the ECM goes to ground activates the solenoid and closes the relay). ALSO from battery C1641-1 red wire to main junction box to fuse 24E (20 amps) to the switched side of relay. When closed it leaves at C0570-88 on a green wire to C2709-1 at the boost pump (M296) out on connector C2709-2 1.5 meters long black wire to a grounding lug.
Sorry for the long explanation, but these things can be frustrating when looking for a reason why they don't work properly.
Hope this helps more than confuses.
Jeff
#3
OK, the ECM controls the brake boost pump.
SHORT ANSWER:
Under the hood in the main junction box Check link 11E, fuse 24E and relay 260. In the Central junction box behind the glove box check fuse 28P, and all the wires in between. Oh, and the pump itself.
LONG ANSWER:
From the battery connector C1631 pin 1 red wire runs to C0632-1 in the under hood junction box. From there it runs thru link 11E (30 amps) to C0570-114 a brown wire to C0028-4 (ignition switch S176) When in the cranking mode it leaves C0028-7 white and red? wire to C00582-5 at the central junction box behind the glove compartment to fuse 28P (5 amps) out C0583L-35 green wire and back to the main junction box C0570-69 to one side of the relay R260 solenoid then C0570-71 green and white wire to ECM CC0635L-16 (presumably the ECM goes to ground activates the solenoid and closes the relay). ALSO from battery C1641-1 red wire to main junction box to fuse 24E (20 amps) to the switched side of relay. When closed it leaves at C0570-88 on a green wire to C2709-1 at the boost pump (M296) out on connector C2709-2 1.5 meters long black wire to a grounding lug.
Sorry for the long explanation, but these things can be frustrating when looking for a reason why they don't work properly.
Hope this helps more than confuses.
Jeff
SHORT ANSWER:
Under the hood in the main junction box Check link 11E, fuse 24E and relay 260. In the Central junction box behind the glove box check fuse 28P, and all the wires in between. Oh, and the pump itself.
LONG ANSWER:
From the battery connector C1631 pin 1 red wire runs to C0632-1 in the under hood junction box. From there it runs thru link 11E (30 amps) to C0570-114 a brown wire to C0028-4 (ignition switch S176) When in the cranking mode it leaves C0028-7 white and red? wire to C00582-5 at the central junction box behind the glove compartment to fuse 28P (5 amps) out C0583L-35 green wire and back to the main junction box C0570-69 to one side of the relay R260 solenoid then C0570-71 green and white wire to ECM CC0635L-16 (presumably the ECM goes to ground activates the solenoid and closes the relay). ALSO from battery C1641-1 red wire to main junction box to fuse 24E (20 amps) to the switched side of relay. When closed it leaves at C0570-88 on a green wire to C2709-1 at the boost pump (M296) out on connector C2709-2 1.5 meters long black wire to a grounding lug.
Sorry for the long explanation, but these things can be frustrating when looking for a reason why they don't work properly.
Hope this helps more than confuses.
Jeff
And thank you for reply, I have power at fuse 28 and 24, does that mean the link is good?
And I still don't know what Relay you are referring to? I don't have relay 260.
Thanks
Adam
#4
Not sure which relay either
Yeah, I know. The wiring diagram calls it R260. You could test it a few ways.
1. Put power to C079L pin 88 and see if pump works.
2. Ground C0570L pin 71 and see if the relay moves.
3. Ground C0570L pin 71 test for power at C0570L pin 88
4. Do step 1. then step 2. and if you get power, start pulling relays until you loose power. Then you will know which one it is.
AND when you find out lets me know because I don't know which one it is either.
1. Put power to C079L pin 88 and see if pump works.
2. Ground C0570L pin 71 and see if the relay moves.
3. Ground C0570L pin 71 test for power at C0570L pin 88
4. Do step 1. then step 2. and if you get power, start pulling relays until you loose power. Then you will know which one it is.
AND when you find out lets me know because I don't know which one it is either.
#5
Yeah, I know. The wiring diagram calls it R260. You could test it a few ways.
1. Put power to C079L pin 88 and see if pump works.
2. Ground C0570L pin 71 and see if the relay moves.
3. Ground C0570L pin 71 test for power at C0570L pin 88
4. Do step 1. then step 2. and if you get power, start pulling relays until you loose power. Then you will know which one it is.
AND when you find out lets me know because I don't know which one it is either.
1. Put power to C079L pin 88 and see if pump works.
2. Ground C0570L pin 71 and see if the relay moves.
3. Ground C0570L pin 71 test for power at C0570L pin 88
4. Do step 1. then step 2. and if you get power, start pulling relays until you loose power. Then you will know which one it is.
AND when you find out lets me know because I don't know which one it is either.
Thanks again for reply
This is way above my skill level 🤣 The relay with the Key picture is the immobilizer right? So it shouldn't be that one!?
How likely is it the the ECM is bad? I'm hoping not, the is another whole level I don't want to get into!
Thanks again
Adam
#6
Hi. I'm not sure if you're still working on this issue, but I had the same challenge today.
Relay 11 in the Engine Compartment Fuse Box is the "Relay 260" mentioned in the wiring diagrams.
To check the wiring to the pump, you can check for continuity from one of the terminals of the relay socket (the one closest to the center of the engine compartment) to the green wire on the plug to the vacuum pump.
On mine the pump only runs for a few seconds on startup, so it could be easy to miss.
Relay 11 in the Engine Compartment Fuse Box is the "Relay 260" mentioned in the wiring diagrams.
To check the wiring to the pump, you can check for continuity from one of the terminals of the relay socket (the one closest to the center of the engine compartment) to the green wire on the plug to the vacuum pump.
On mine the pump only runs for a few seconds on startup, so it could be easy to miss.
Thread
Thread Starter
Forum
Replies
Last Post