REV MS2 Enhanced VVT on 03 Special Edition no 12v switched
#1
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So I've spent most of the day trying to figure out why I can't get my MS2 to power up. Hoping for some help here.
So far this is what I've verified:
- Continuity from pin 4AF on MS2 female ecu connector to pin 28 on DB 37 main connector.
- No 12v power coming from pin 4AF with no ECU installed and key on.
- Positive 12v on pin 4AF with OEM ecu installed.
- Jumpering main relay sends 12v to pin 4af and powers up MS2 and car starts and runs with MS2.
There was a dealer installed alarm system, but I removed it but still no fix.
Also noticed in the TunerStudio dashboard that the clutch and neutral safety switches seem to be reversed. I.E when you press the clutch in the neutral indicator turns green and when you put the transmission in neutral the clutch indicator lights up green. Don't know if it's related or not though.
So far this is what I've verified:
- Continuity from pin 4AF on MS2 female ecu connector to pin 28 on DB 37 main connector.
- No 12v power coming from pin 4AF with no ECU installed and key on.
- Positive 12v on pin 4AF with OEM ecu installed.
- Jumpering main relay sends 12v to pin 4af and powers up MS2 and car starts and runs with MS2.
There was a dealer installed alarm system, but I removed it but still no fix.
Also noticed in the TunerStudio dashboard that the clutch and neutral safety switches seem to be reversed. I.E when you press the clutch in the neutral indicator turns green and when you put the transmission in neutral the clutch indicator lights up green. Don't know if it's related or not though.
#3
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Got it sorted. Thanks to Dimitris!
My car is a late model 03 and apparently there was a change in mid 03 as to how the main relay is activated. I'm pasting Dimitris' email below. BTW I'm totally blown away with Dimitris' knowledge and support, I purchased this MS2 from another forum member and Dimitris has still answered my questions. Top notch customer service!
That explains it. On the 01-03, the main relay is activated by the ignition switch.
On the 03+, it is activated by the ECU itself. If the ECU is order for a 03+, I install a circuit inside the ECU to activate the relay.
However, you can wire in an additional relay on the wiring harness, which will activate the main relay.
You will need a standard 4-pole automotive relay, which has the 85, 86, 87, 30 contacts labelled.
Connect 85 to pin 4S on the harness.
Connect 86 to 4A
Connect 87 to 3H
Connect 30 to 4A
This will activate the main relay as soon as you switch the ignition on.
Worked perfectly!
My car is a late model 03 and apparently there was a change in mid 03 as to how the main relay is activated. I'm pasting Dimitris' email below. BTW I'm totally blown away with Dimitris' knowledge and support, I purchased this MS2 from another forum member and Dimitris has still answered my questions. Top notch customer service!
That explains it. On the 01-03, the main relay is activated by the ignition switch.
On the 03+, it is activated by the ECU itself. If the ECU is order for a 03+, I install a circuit inside the ECU to activate the relay.
However, you can wire in an additional relay on the wiring harness, which will activate the main relay.
You will need a standard 4-pole automotive relay, which has the 85, 86, 87, 30 contacts labelled.
Connect 85 to pin 4S on the harness.
Connect 86 to 4A
Connect 87 to 3H
Connect 30 to 4A
This will activate the main relay as soon as you switch the ignition on.
Worked perfectly!
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