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Everything posted by OldCadTech

  1. @KHE That was me. I pulled them out the top. The trouble is access to the lower brackets and exhaust etc.. requires some swivel sockets and access without a hoist would be a problem, not impossible but problematic. If you want to PM me I can give you my contact # easier to explain over the phone.
  2. I'm thinking, passenger side wiring damage at the A-pillar kick panel or damaged BCM. The bulkhead connector / pass-thru probably got pulled pretty hard. Body shop may have missed reconnecting a ground wire either the one that Logan referenced or the passenger side wiring harness to the rear.
  3. Wow! I really hope the multifunction switch is the problem. Again, how did you verify the switch was bad? Throwing parts at a problem until it is fixed or you run out of money is not diagnosis. On a vehicle that has had major damage and deployed the air bags, the multi-function switch would be at best a 40% chance of being defective IMO. The drivers air bag could possibly have damaged the column enough, or excessive driver contact during the accident, so I might give it a 50% chance. The DRL's should go out in park with the parking brake set. I wish you luck...
  4. @rhdsts You shouldn't feel bad at all, and you didn't waste anyones time. Thursdays are a late night for me, so a little delay in getting back to you. To me it looks a lot like rodent damage. Do you have rodents in Australia? You know the small ones, not the ones with the big feet.. JK You did good, congratulations, fine job! I love a happy ending. Those connectors are easy to find, at least they are here anyway. There is a special tool to get the wire out of the connector and another special crimp tool as well. Not very expensive tools.
  5. Looks like an aftermarket repair kit is only option. AutoZone, Parts Geek, CarID
  6. I was on the way to bed, then I thought - be sure to test the switch when the booster is fully charged or pressurized first, it should be an open circuit. Again, make the tests with the connectors disconnected. Okay, I'm going....
  7. Wait one, I think I got the test written wrong it's 12:55am here. Yes I did, If the booster is discharged there should be continuity. Sorry about that I corrected the statement above also.
  8. One more thing be sure to check the things that @rockfangd suggested as a lot of GM circuits share components. This is noted in the schematic where it references to check the power distribution
  9. @rhdsts discharge the booster pressure by applying the brake several times and test for continuity between terminals A and B, it should have continuity if it does not have continuity with the booster pressure discharged then the switch is defective.
  10. @rhdsts ohm test the pump motor from terminals C to B . Post what you have for resistance.
  11. So lets get off the dead horse and diagnose the problem rather than whether or not the diagram is correct. The relay is normally open at high fluid pressure, which is the normal operating, non-energized condition. When the pressure drops, the switch is closed the relay is energized and the pump runs, "builds pressure and the circuit opens again". Mr Logan, as far as your rant is concerned, if this statement was directed at me, I can explain exactly how the system operates. Please PM me and I will explain it to you. NO and NC relays and switches ( the PBPSwitch is a hydraulically controlled switch NOT electrical it only makes or breaks the circuit like a button ) are exactly the diagnostic point. If the pressure is high and the pressure switch is connected or ( closed ) then there will be a direct path to ground and the fused test will blow the fuse. Mr Logan, In reference to your other rant about the PCM or BCM. The OP stated there was a key on pump test. I stated that if there was a key-on test regardless of the system pressure, then there would have to be another way to control the ground to energize the relay, possibly at splice 130. How do you get key on engine off then? So, with the horse, hopefully, now buried, the pump motor or the pressure switch can not be tested with the connector connected. ALL GM schematics show the circuit in a normal non-energized state, unless it is otherwise noted. Again, Mr Logan, PM me and I will help you with GM electrical schematics. I've been reading and understanding GM electrical schematics for a long time.
  12. @rhdsts This may help you understand the importance of normally open or normally closed. It all depends on the energized state. http://www.galco.com/comp/prod/relay.htm
  13. This test can be misleading, doing an ohm check, as the DVOM supplies a small voltage to the circuit. The tests at the pump and switch connectors should be done with the connectors disconnected. An ohm check of the pump itself would be valid. Do the check between circuits B & C at the unit with the terminal connector disconnected.
  14. Whether it is a normally open or normally closed switch makes diagnosis of a short to ground important. Logan is correct in the operation of the switch, but my point is, the switch is normally open unless the load is needed and then the circuit is energized, then the circuit opens back to a "normal" state. I'm not sure that the test you performed indicated a faulty pump or a faulty switch.
  15. LOL - Looking again, If you have service manual access look for the ground distribution. There has to be another control of the ground, perhaps on splice 130. Fuse 11 10A is only hot in key on and start, not run, unless you consider that is a FSM error also. There is a key on run test, if the switch is normally closed the relay would not provide power while the key is in run if the pressure was above the low limit of the switch.
  16. Please look again. The terminal B at the pump is a direct path to ground G-106 from the pump motor. With the pressure switch open the PCM or BCM, whichever has control, can still command the relay and run the key on pump test through the 25A fuse at the rear fuse block. The 25A fuse is hot at all times and only needs the relay coil to complete the path The pressure switch is another path for power when needed by pressure demands, or as a parallel circuit for fail safe.
  17. The pump is an on demand pump. If the PBB P/Switch is normally closed the pump would run constantly. Completing the circuit and supplying power and ground. If power is supplied to the Pink wire circuit #173 or connector C at the pump motor there is a ground circuit at the connector B terminal without the pressure switch being closed. I would imagine this circuit is the pump run circuit at key on. Yes, there are mis-prints esp the vacuum sensor signal. I don't have the FSM. FSM errors were a problem year after year. It was not that rare in the past, hopefully there have been improvements.
  18. In the 1st post diagram the pump doesn't turn on until the switch closes then the relay coil is energized and the coil pulls the relay switch closed.
  19. If you did the same test on the new pump and the fuse did not blow, I would replace the unit also.
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