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1997 C5, crank no start. Fuel pump, horn and ac clutch activated with key out of the ignition. Back story the car is in the Philippines and has not run for 3 years. The horn isn't working and fuel pump is not supplying fuel. I replaced the bcm and the horn and ac compressor relays are still activated. The fuel pump relay doesn't seem to be activated. Not crank no start, vats I'm sure. I try to do the vats re learn procedure now. Any ideas on the relays being activated when the keybis out of the ignition switch?
You’re saying it a crank no start and then you’re saying later it’s a “Not crank, no start”…so which is it ??…you have to be VERY specific when explaining your concern…what does “the fuel pump relay doesn’t seem to be activated”…did you swap the relay with another one ??…also relays are not activated when the key is out of the ignition…how much electrical and diagnostic experience do you have ??…I think this diagnostic may be over your head…do you hear the fuel pump prime for 2 seconds when you turn the key on ??…scratching my head when you said “fuel pump, AC clutch and horn activated with key out of ignition…what does mean ???…was the new BCM programmed ??…it is not plug and play.
You’re saying it a crank no start and then you’re saying later it’s a “Not crank, no start”…so which is it ??…you have to be VERY specific when explaining your concern…what does “the fuel pump relay doesn’t seem to be activated”…did you swap the relay with another one ??…also relays are not activated when the key is out of the ignition…how much electrical and diagnostic experience do you have ??…I think this diagnostic may be over your head…do you hear the fuel pump prime for 2 seconds when you turn the key on ??…scratching my head when you said “fuel pump, AC clutch and horn activated with key out of ignition…what does mean ???…was the new BCM programmed ??…it is not plug and play.
If you read my post again I said after swapping the bcm it won't crank.
And the fuel pump relay doesn't seem to be activated because when I plug it back in it doesn't click like the horn and ac compressor relays.
Like i said with the key out of the ignition the relays are activated.
The fuel pump isn't supplying pressure. Power is coming out of the relay with the original bcm installed. Im not sure if the pump is getting power yet. I'll work on that after I figure out the other issues. No it doesn't prime.
When I say the relays are activated with the key out of the ignition, I mean there is power out of the relays to the horn, ac compressor and fuel pump. With the the original bcm installed.
The bcm in 1997 does not have to be programmed to make it run.
I still don’t know what you mean by “relays are ACTIVATED” when key out of the ignition…a relay has a load and control side…please watch some YouTube videos on how relays work and how to test them…you are telling me that by being “activated” whatever that means that the horn is continuously blowing, the AC Clutch is staying engaged and the fuel pump relay continuously runs which it doesn’t…please explain what activated means referring to relays.
You’re saying it a crank no start and then you’re saying later it’s a “Not crank, no start”…so which is it ??…you have to be VERY specific when explaining your concern…what does “the fuel pump relay doesn’t seem to be activated”…did you swap the relay with another one ??…also relays are not activated when the key is out of the ignition…how much electrical and diagnostic experience do you have ??…I think this diagnostic may be over your head…do you hear the fuel pump prime for 2 seconds when you turn the key on ??…scratching my head when you said “fuel pump, AC clutch and horn activated with key out of ignition…what does mean ???…was the new BCM programmed ??…it is not plug and play.
Originally Posted by mmartinez
As stated previously in earlier post, a new BCM has to go thru a relearn procedure if not the the car will not crank over.
Yes, I understand this but the relays supplying power to the ac compressor, horn and fuel pump constantly with the key out of the ignition is my concern.
I still don’t know what you mean by “relays are ACTIVATED” when key out of the ignition…a relay has a load and control side…please watch some YouTube videos on how relays work and how to test them…you are telling me that by being “activated” whatever that means that the horn is continuously blowing, the AC Clutch is staying engaged and the fuel pump relay continuously runs which it doesn’t…please explain what activated means referring to relays.
Yes the horn would be honking all the time if it wasn't burnt out. And yes currently the fuel pump would be running also but I think it's burnt out too. And yes the ac clutch is on all the time.
Maybe I'm not saying it right but all three relays are triggered all the time sending out power.
Here is the wiring diagram so if you have a 12 volt test light and know how to test both the load and control sides of that particular relay you can diagnose it easily…the load side of the horn relay is “hot at all times”…the other 2 are “hot in “run or start”…if the control side of the relay is “ground side switched” you hook the test light to B+ to check terminal 85…if it is “power side switched” you test terminal 86 by hooking the test light to ground…fuel pump is power side switched and horn and AC are “ground side switched”…if this confuses you diagnosing this testing will be impossible for you.
Crank no start
