How do I ?
Thread Starter
Supreme Member
Joined: Jul 2001
Posts: 2,398
Likes: 1
From: Baton Rouge ,Louisiana ,USA
How do I ?
How do I check the MAF singnal wire at the ECM connector ?
I have a multimeter and test like , But Im pretty much ignorant when it comes to using them ? Do I test it with the car running ? or just ignition on ? Should I test it with my test light or multimeter ? Do I probe this wire to check it . Please give me pretty detail instructions . Thanx alot guys and please excuse me for my ignorance .
I have a multimeter and test like , But Im pretty much ignorant when it comes to using them ? Do I test it with the car running ? or just ignition on ? Should I test it with my test light or multimeter ? Do I probe this wire to check it . Please give me pretty detail instructions . Thanx alot guys and please excuse me for my ignorance .
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Joined: Jan 2000
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Wayne,
Get out your handy meter. You'll be testing the MAF output voltage with the engine running. Before you can do that, you'll have to connect your meter leads to the MAF harness. The easiest way is to back-probe the wiring harness connector at the MAF sensor itself. You can use specially made back-probe adapters, paper clips sharpened to a point, dressmakers' pins, or your meter probes themselves if they are slender enough. Connect the negative (black) probe to the 'A' terminal of the MAF. Connect the positive (red) probe to the 'C' terminal. Ber certain that you don't short the probes together or allow the 'C' terminal to contact a ground, since you risk damaging the MAF output circuitry.
To help identify the connectors if the letters are not easy to see, the 'A' terminal should have a black/white wire, and the 'C' terminal should have a dark green wire.
Once the probes are connected and secured so they don't short, start the engine and monitor the output voltage on a 2 VDC scale. It doesn't matter if the engine is warmed or not, since input air mass isn't temperature dependent.
Here's what I got on a 305:
Get out your handy meter. You'll be testing the MAF output voltage with the engine running. Before you can do that, you'll have to connect your meter leads to the MAF harness. The easiest way is to back-probe the wiring harness connector at the MAF sensor itself. You can use specially made back-probe adapters, paper clips sharpened to a point, dressmakers' pins, or your meter probes themselves if they are slender enough. Connect the negative (black) probe to the 'A' terminal of the MAF. Connect the positive (red) probe to the 'C' terminal. Ber certain that you don't short the probes together or allow the 'C' terminal to contact a ground, since you risk damaging the MAF output circuitry.
To help identify the connectors if the letters are not easy to see, the 'A' terminal should have a black/white wire, and the 'C' terminal should have a dark green wire.
Once the probes are connected and secured so they don't short, start the engine and monitor the output voltage on a 2 VDC scale. It doesn't matter if the engine is warmed or not, since input air mass isn't temperature dependent.
Here's what I got on a 305:
Thread Starter
Supreme Member
Joined: Jul 2001
Posts: 2,398
Likes: 1
From: Baton Rouge ,Louisiana ,USA
Thanx Vader . I disconected the a-b terminal connector on the ECM . I then turn the ignition on but did not start the car . I only got a light on one socket . Im starting to think it is a bad b connector which hooks into my ECM ...Sence I only got one light on the b connector does this mean my b connector is bad ? Thanx . I had done this prior to what you told me to do . Thanx for the pics though , and the advice , I will print it off for future use .
