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Throttle Body Issue

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Old Sep 17, 2024 | 06:22 PM
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Default Throttle Body Issue

I recently put an LS3 in my 2004 Z06 and I didn't touch anything on the factory harness and now I have no voltage to the connector that plugs into the throttle body. I'm running an LS2 throttle body with the adapter harness I'm just not sure what could have happened, the car ran fine before the engine swap. Any input would be appreciated.
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Old Sep 17, 2024 | 07:46 PM
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So you don’t have 5 volts on the dark green and yellow/black wires from the OE harness on the TPS sensor if that’s what you’re taking about ??
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Old Sep 17, 2024 | 07:46 PM
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Did you rule out the adapter harness being an issue?
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Old Sep 17, 2024 | 08:08 PM
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yes, there is no voltage on the factory connector without the adapter hooked up
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Old Sep 17, 2024 | 08:10 PM
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Originally Posted by Gcallahan123*
yes, there is no voltage on the factory connector without the adapter hooked up
Are you seeing both 5 volt references AT the TAC Module then ??
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Old Sep 17, 2024 | 08:13 PM
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There is not 5v on the green or yellow and black wires
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Old Sep 17, 2024 | 08:14 PM
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Originally Posted by Gcallahan123*
There is not 5v on the green or yellow and black wires
Have you checked at the TAC Module ??…that is where the 5 volts comes from.
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Old Sep 17, 2024 | 08:17 PM
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Old Sep 17, 2024 | 08:18 PM
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I'm going to get the pinout on the TAC module tomorrow to check that, unless you know what pins are 5V and ground
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Old Sep 17, 2024 | 08:19 PM
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Thanks
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Old Sep 17, 2024 | 08:21 PM
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Originally Posted by Gcallahan123*
I'm going to get the pinout on the TAC module tomorrow to check that, unless you know what pins are 5V and ground
I mentioned which 2 wires are the 5 volt references.
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Old Sep 17, 2024 | 08:24 PM
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Originally Posted by Gcallahan123*
I'm going to get the pinout on the TAC module tomorrow to check that, unless you know what pins are 5V and ground
These are 2 potentiometers…5 volt reference, signal, and ground !!…let me post the OE wiring…I see a mistake on the color redrawn !!
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Old Sep 17, 2024 | 08:28 PM
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You may want to check Fuse 17 !!


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Old Sep 18, 2024 | 02:42 PM
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I have gone thru all the wires from the TAC to the TPS connector and they all have continuity along with the ground on the block. I don't have any voltage at the TAC connector on the pink ignition wire or the 2 DK Green and Dk Blue wires. I also tried checking for 12V on the Pink ignition wire with plug disconnected from the TAC and still have nothing, fuse 17 is good, I'm at a lose.
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Old Sep 18, 2024 | 02:52 PM
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Remove the fuse and either with a DVOM or test light see if you have power on at least one of those 2 terminals with the key ON !!…with a test light if the fuse is good the test light should illuminate on both fuse test points..it is hot in START or ON.
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Old Sep 18, 2024 | 03:04 PM
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I do have 12V on one leg with the fuse out
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Old Sep 18, 2024 | 03:18 PM
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Originally Posted by Gcallahan123*
I do have 12V on one leg with the fuse out
Ok, do you have a good feed on one leg and if the fuse is good and still no power out backprobe that pink wire with the connector reinstalled…if you can 100% verify 12 volts is getting into the TAC module but nothing coming out it may be a bad module…I believe it is just one power source but let me check wiring.
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Old Sep 18, 2024 | 03:23 PM
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I'm not getting 12V on the pink wire with connector removed, with the key on I should be getting a voltage there even with it unplugged shouldn't I?
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Old Sep 18, 2024 | 03:29 PM
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Originally Posted by Gcallahan123*
I'm not getting 12V on the pink wire with connector removed, with the key on I should be getting a voltage there even with it unplugged shouldn't I?


Yes, power goes through the fuse to the end of the connector and then into the module when you connect it and then 5 volts out..make sure you have continuity from the one leg of the fuse to the connector…see if your DVOM will reach from the fuse box to the connector… you may have a broken wire from the fusebox to the connector.
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Old Sep 18, 2024 | 03:35 PM
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If you can pierce the wire a 1/4 from the connector see if you have power..suggest you back probe at the pink wire terminal…wire may be broken inside the connector where you can’t see it !!
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