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Did I "Smoke" my ECM

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Old Oct 17, 2021 | 04:22 PM
  #1  
austinlandroverbill's Avatar
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Rock Crawling
Joined: Jun 2014
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Default Did I "Smoke" my ECM

OK, here's the situation.

I had 3 codes: a MAF fault (P0102) that I believe was also causing a P0135 and a P0155 (O2 sensor) faults as well. You can see my posts on the MAF (and SAI) over the past couple of days. It was running like it was in limp-home mode, i.e., no power above 2-2,500rpm, stumbling, etc.

I noticed that I also hadn't heard the SAI pump run in a while, so while I was waiting for a new (Bosch) MAF, decided to troubleshoot that.

I assumed (as in "***") that the SM (R2) relay was for the SAI pump as it had an "S" in it. Jumpering the 3-5 blades, discovered that it was the starter motor, not the SAI pump.

I think I also might've jumpered the hot (not sure if it was the 3 or 5 blade) to the 1 or 2 blade to ground because the paper clip I was using heated up like a light bulb -- I have the burned imprint on my thumb and index to prove it.

Fortunately, someone pointed me to the R6 "Engine Thunderbolt" relay, and I was able to test the SAI pump to confirm the pump worked.

Going back to the ODBII, I discovered, I now had like 18 codes, many of which reference a short circuit condition -- for the SAI solenoid, evap purge, evap vent, engine coolant lamp, crankshaft position.

When I got the filament effect on the SM/R1 relay, did I inadvertently fry the ECM? I say this because I know that the way the ECM controls relays it that it opens a bunch (all?) of the relay solenoids to ground on blade 1 or 2 as the way of energizing the relay. Perhaps the 5 or so short circuit codes are related to me having damaged/fused that path that the ECM uses to ground to energize the relays.

If I fried the ECM, is it a hard replacement, does it need to be programmed somehow to the vehicle itself?

The D2 still runs, but now it is making a "popping", muffled backfire kind of noise when I try to accelerate.

Hopefully, someone with intimate knowledge of the ECM can help me decipher what happened (maybe it is a common/share ground path in fuse box?).

Any help here would be most appreciated.


Car Scanner ELM OBD2
DTC report
============1==============
P0102
Raw code: 0102
ECU: OBD-II
Status: Confirmed
OBDII: Mass air flow (MAF) sensor/volume air flow (VAF) sensor - low input

============2==============
P0135
Raw code: 0135
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 1, bank 1, heater control - circuit malfunction

============3==============
P0155
Raw code: 0155
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 1, bank 2, heater control - circuit malfunction

============4==============
P0141
Raw code: 0141
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 1, heater control - circuit malfunction

============5==============
P0161
Raw code: 0161
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 2, heater control - circuit malfunction

============6==============
P1451
Raw code: 1451
ECU: OBD-II
Status: Confirmed
OBDII: Evap Emission Control Sys Vent Control Valve Circuit

============7==============
P0414
Raw code: 0414
ECU: OBD-II
Status: Confirmed
OBDII: Secondary air injection (AIR) solenoid A - short circuit

============8==============
P1482
Raw code: 1482
ECU: OBD-II
Status: Confirmed
OBDII: SCP

============9==============
P0445
Raw code: 0445
ECU: OBD-II
Status: Confirmed
OBDII: Evaporative emission (EVAP) canister purge valve - short circuit

============10==============
P0448
Raw code: 0448
ECU: OBD-II
Status: Confirmed
OBDII: Evaporative emission (EVAP) system, vent control - short circuit

============11==============
P0340
Raw code: 0340
ECU: OBD-II
Status: Confirmed
OBDII: Camshaft position (CMP) sensor A, bank 1 - circuit malfunction

============12==============
P0134
Raw code: 0134
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 1, bank 1 - no activity detected

============13==============
P0154
Raw code: 0154
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 1, bank 2 - no activity detected

============14==============
P0139
Raw code: 0139
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 1 - slow response

============15==============
P0159
Raw code: 0159
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 2 - slow response

============16==============
P0140
Raw code: 0140
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 1 - no activity detected

============17==============
P0160
Raw code: 0160
ECU: OBD-II
Status: Confirmed
OBDII: Heated oxygen sensor (HO2S) 2, bank 2 - no activity detected

============18==============
P1884
Raw code: 1884
ECU: OBD-II
Status: Confirmed
OBDII: Engine Coolant Level Lamp Circuit Short to Ground
 
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Old Oct 17, 2021 | 08:20 PM
  #2  
JohnZo's Avatar
Pro Wrench
Joined: Apr 2021
Posts: 1,411
Likes: 397
From: SE Washington State
Default

Clear the codes first, then see if they return. Maybe was just temporary during your testing work.
 
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