P1351 GMC Code - Ignition Control Module Circuit High Voltage
Quick Answer
The Ignition Control Module (ICM) has independent power and ground circuits. Common causes include Faulty Ignition Control Module, Ignition Control Module harness is open or shorted, Ignition Control Module circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P1351 GMC indicates Ignition Control Module Circuit High Voltage.
- Common causes
- Common causes include Faulty Ignition Control Module, Ignition Control Module harness is open or shorted, Ignition Control Module circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P1351 GMC Description
-The ignition control (IC) timing signal
-The IC timing control
-The low resolution engine speed signal
-The medium resolution engine signal
-The camshaft position signal
-The low reference
The ICM sends 3X signals to the PCM, and controls the timing advance during engine cranking. The timing advance changes to PCM control after the following actions occur:
The PCM receives the second 3X signal
The PCM applies 5 volts to the ignition control (IC) timing signal circuit.
The ICM monitors the CKP sync signal when the engine is cranking. The CKP sync signal is passed from the CKP sensor to the ICM on the CKP sensor 2 signal circuit. The CKP sync signal is used to determine the correct cylinder pair and initiate the ignition coil firing sequence. The 18X reference pulses are passed from the CKP sensor to the ICM on the CKP sensor 1 circuit. The 18X reference pulses are used for fuel injection and ignition control. After the ICM receives both signals, the ICM passes the 18X and 3X reference signals to the PCM. The CMP and the CKP sensors share a 12 volt reference and low reference circuit. The CKP sensor consists of the following circuits:
-A 12 volt reference
-A low reference
-A CKP sensor 1 signal
-A CKP sensor 2 signal
What are the Possible Causes of the DTC P1351 GMC?
- Faulty Ignition Control Module
- Ignition Control Module harness is open or shorted
- Ignition Control Module circuit poor electrical connection
How to Fix the DTC P1351 GMC?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1351 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P1351 GMC Code
What does the OBDII code P1351 mean for a GMC vehicle?
The P1351 code indicates a high voltage condition in the ignition control module circuit, often related to the ignition system.
What are the common symptoms of a P1351 code in a GMC?
Symptoms may include engine misfires, rough idling, difficulty starting, reduced power, or the check engine light being illuminated.
What causes the P1351 code to appear on a GMC?
Common causes include a faulty ignition control module, damaged or corroded wiring in the ignition circuit, a failing ignition coil, or issues with the powertrain control module (PCM).
Can a bad ignition coil trigger the P1351 code?
Yes, a failing ignition coil can cause incorrect voltage levels, which may trigger the P1351 code.
How can I diagnose the P1351 code on a GMC?
Start by inspecting the ignition control module, wiring, and connectors for damage or corrosion. Use a multimeter to test for proper voltage and continuity in the circuit.
Can I drive my GMC with a P1351 code?
Driving with a P1351 code is not recommended, as it can lead to further engine damage, reduced performance, or potential stalling.
How do I fix the P1351 code on a GMC?
Repairs may include replacing the ignition control module, repairing damaged wiring, replacing the ignition coil, or reprogramming the PCM if necessary.
Does the P1351 code always mean the ignition control module is bad?
No, the code could also be caused by wiring issues, a faulty ignition coil, or problems with the PCM, so proper diagnosis is essential.
Will clearing the P1351 code fix the issue?
Clearing the code may turn off the check engine light temporarily, but the issue will likely return unless the underlying problem is resolved.
How much does it cost to repair a P1351 code on a GMC?
Repair costs vary depending on the root cause but typically range from $100 to $400, including parts and labor.
Discuss the causes and fixes for P1351 GMC OBDII Code
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WHO cares what vehicle gets this code its a short in the ignition circuit most likely the icm is done or the icm wrire to` computer main` vcm is bare open,bad connection ;green/if the rest of the ignition circuit harness tests good peroid....unless the vehicle has a security system;dash lights security with key just on.......GM hint pink or yellow wires check......4.0 volts target different means a problem..... other vehicles check your ohm or volt readingfpr test and wire colours
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I'm getting this code ever since I did a tune up and replaced the ICM. The truck runs good, but every once in a while it'll have trouble starting. It'll start for a split second and die, then I'll turn it off and start it with no problem other than it sounds like it's having a little trouble for a few seconds. I don't know where to start.
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I have the same symptoms but the service engine light comes and goes. I haven't done a thing to my truck yet. 1998 Chevy suburban 7.4. Every so often it tries to start and dies. Then it fires right up and runs fine. I'm thinking I have a bad ground or a loose connection somewhere because the service engine light will go off for a day or two at a time.
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The most common problem for your 98 Suburban with the 7.4L engine is the Ignition Control Module.
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I have a 96 GMC just bought it Monday, don’t know engine size. I have had the issue of it turns over but won’t start. Turn it off, it starts and dies, turn it off again and it starts and runs fine. Today it cut out, ran poorly, and died. I put new fuel filter on, the old one was mostly plugged. It started hard, but had no power, eventually died. Pulled the codes. P0102, mass or volume air flow A circuit low, P0131 O2 sensor circuit low, voltage bank 1 sensor 1, P1351, manufacturer control. Any thoughts or pointers appreciated.
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Have you tried clearing the codes? what code comes back first? The O2 sensor will not cause the no start situation, you may either have a problem with the Mass Air Flow (MAF) sensor or the Ignition Control Module, both components could cause the no start or no power problem.
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I have not checked to see which one comes back first, I will do that. Thank you.
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Just checked my codes, only one is the ICM. thanks, I’ll see if that works.
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I checked rock auto, $42, O Reilies $88, Carquest $84, guess I’ll wait for Rock Auto.
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